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Chinese Journal of Chemistry 2022年第12期40卷 1478-1491页

作者： Yijun Dong siqi zhang Liang Zhao School of Life Sciences Tsinghua UniversityBeijing 100084China Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China

Iron-sulfur(Fe-S)proteins are among the most common type of natural metalloproteins that participate in a large range of key metabolic *** date,enormous research works on the exploration of protein structures and catalytic mechanisms have revealed that the active sites are generally composed of a Fe-S cluster and a highly conserved coordination ***,people are enlightened by the prebiotic evolution of an-cient clusters and are dedicated to the development of biosynthetic methods for modern *** review aims to systemically summarize the structural development of peptide-coordinated iron-sulfur clusters from two perspectives:"bottom-up"approaches involving evolution of prebiotic chemical synthesis for natural proteins and"top-down"analyses of biosynthesis in modern biological systems for artificial ***,current challenges and the direction of future development are also presented to provide new perspectives of developing enzyme mimics and further mechanistic studies.

关键词： Peptides Iron-sulfur clusters Prebiotic evolution Biosynthesis Biomimetic synthesis

Metal-Ligand Cooperative Effect on Intramolecular Electron Transfer in Macrocycle-Encircled Copper-Oxygen Species

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CCS Chemistry 2023年第9期5卷 2171-2183页

作者： siqi zhang Liang Zhao Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084

Reproduction of ubiquitous metal-ligand cooperativity in copper-oxygen enzyme mimics is crucial for the comprehension of catalytic mechanisms in coppercontaining enzymes and copper-catalyzed chemical *** we describe the synthesis and reduction behavior of a series of encapsulated dinuclear copper-oxygen species by systematically altering the size and geometric structure of peripheral macrocyclic *** with the occurrence of a single-electron reduction,these macrocycleencircled dicopper complexes show distinct electron transfer pathways as a function of differently sized and substituted macrocyclic *** structural characterization and density functional theory calculations reveal that a coupled metal-ligand and bimetallic cooperativity is involved in the singleelectron reductionof hydroxyl-bridged dicopper species within macrocyclic homologue ligands Py[7]Ph[1]and Py[7]Ph[1]-*** highly flexible configurations of macrocyclic ligands are conducive to stabilizing copper-oxygen intermediates with different valence states and facilitating an intramolecular electron transfer between macrocyclic ligands and the central copper-oxygen *** of biased electron transfer behaviors of copper-oxygen species with their peripheral macrocyclic ligands provides a new means of tuning redox properties of metal cluster species and opens a broader prospect on the mechanistic study of copper-containing enzymes and copper-catalyzed transformations.

关键词： metal-ligand cooperativity bimetallic cooperativity macrocyclic ligands copper-oxygen species intramolecular electron transfer

A Modeling Method for Predicting the Strength of Cemented Paste Backfill Based on a Combination of Aggregate Gradation Optimization and LSTM

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Journal of Renewable Materials 2022年第12期10卷 3539-3558页

作者： Bo zhang Keqing Li siqi zhang Yafei Hu Bin Han School of Civil and Re source Engineering University of Science and Technology Beijing Beijing100083China Key Laboratory of Ministry of Educ ation of China for Eficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China

Cemented paste backill(CPB)is a susta inable mining technology that is widely used in mines and helps to improve the mine *** investigate the relationship between aggregate grading and different affecting factors and the uniaxial compressive strength(UCS)of the cemented paste backill(CPB),Talbol gradation theory and neural networks is used to evaluate aggregate gradation to determine the optimum aggregate *** mixed aggregate ratio with the least amount of cement(waste stone content river sand content=7:3)is obtained by using Talbol grading theory and pile compactness function and combined with *** addition,the response surface method is used to design strength speaific ratio *** UCS prediction model which ues the ISTM and considers the aggregates gradation have high *** root mean square error(RMSE)of the prediction results is 0.0914,the coefficient of determination(R^(2))is 0.9973 and the variance account for(VAF)is *** with back propagation neural network(BP-ANN),extreme lea ming machine(ELM)and madal basis function neural network(RBF ANN),LSTM can efectively characterize the nonlinear relationship between UCS and individual affecting factors and predict UCS with high *** sensitivity analysis of different affecting factors on UCS shows that all 4 factors have significant effect on UCS and sensitivity is in the following ranking:cement content(0.9264)>slurry concentration(0.9179)>aggregate gradation(waste rodk content)(0.9031)>curing time(09031).

关键词： Backill aggregate gradation machine learning uniaxial compressive strength cemented paste backill

SOLIDIFYING　STRUCTURES　OF　Al_2O_3　SHORT　FIBER／Al－Si　ALLOY　MATRIX　COMPOSITE　PREPARED　BY　SQUEEZE　CASTING

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中国有色金属学会会刊：英文版 1995年第3期5卷 133-135页

作者： zhang, siqi Huang, Jinsong Shen, Jian Lu, Bin Xu, Guofu Central South Univ of Technology Changsha China

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ＳＯＬＩＤＩＦＹＩＮＧＳＴＲＵＣＴＵＲＥＳＯＦＡｌ_２Ｏ_３ＳＨＯＲＴＦＩＢＥＲ／Ａｌ－ＳｉＡＬＬＯＹＭＡＴＲＩＸＣＯＭＰＯＳＩＴＥＰＲＥＰＡＲＥＤＢＹＳＱＵＥＥＺＥＣＡＳＴＩＮＧ￥Ｚｈａｎｇ，Ｓｉｑｉ；Ｈｕａｎｇ，Ｊｉｎｓｏｎｇ；Ｓｈｅｎ，Ｊｉａｎ；...

关键词： composite short fiber Al-Si alloy solidifying structures squeeze casting

Robust magnetic laccase-mimicking nanozyme for oxidizing o-phenylenediamine and removing phenolic pollutants

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Journal of Environmental Sciences 2020年第2期32卷 103-111页

作者： siqi zhang Feifei Lin Qipeng Yuan Juewen Liu Ye Li Hao Liang State key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Department of Chemistry and Waterloo Institute for Nanotechnology University of WaterlooWaterlooOntario N2L 3G1Canada Department of Biotechnology Beijing PolytechnicYi Zhuang Economic and Technological Development ZoneBeijing 100176China

In this study, we report a novel magnetic biomimetic nanozyme(Fe3O4@Cu/GMP(guanosine5′-monophosphate)) with high laccase-like activity, which could oxidize toxic ophenylenediamine(OPD) and remove phenolic *** magnetic laccase-like nanozyme was readily obtained via complexed Cu2+and GMP that grew on the surface of magnetic Fe3O4 *** prepared Fe3O4@Cu/GMP catalyst could be magnetically recycled for at least five cycles while still retaining above 70% *** a laccase mimic,Fe3O4@Cu/GMP had more activity and robust stability than natural laccase for the oxidization of ***3O4@Cu/GMP retained about 90% residual activity at 90℃ and showed little change at pH 3–9, and the nanozyme kept its excellent activity after long-term ***, Fe3O4@Cu/GMP had better activity for removing phenolic compounds, and the removal of naphthol was more than 95%.Consequently, the proposed Fe3O4@Cu/GMP nanozyme shows potential for use as a robust catalyst for applications in environmental remediation.

关键词： Nanozymes Laccase o-Phenylenediamine Phenolic compounds Magnetic nanoparticles

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中医调控自噬防治阿尔茨海默病实验研究进展

辽宁中医药大学学报 2025年第1期27卷 97-101页

作者：张译丹张淼张思琪胡晓阳黑龙江中医药大学黑龙江哈尔滨150006 黑龙江中医药大学附属第二医院黑龙江哈尔滨150001

阿尔茨海默病(alzheimer's disease,AD)是一种进行性神经退行性疾病,其致病因素多、病理机制复杂,涉及到多个生物学过程和分子机制的紊乱。中医的治疗理念强调整体观念和个体化治疗,能够针对AD的多个病理环节进行干预,提高患者的生活质... 详细信息

阿尔茨海默病(alzheimer's disease,AD)是一种进行性神经退行性疾病,其致病因素多、病理机制复杂,涉及到多个生物学过程和分子机制的紊乱。中医的治疗理念强调整体观念和个体化治疗,能够针对AD的多个病理环节进行干预,提高患者的生活质量。许多研究表明,自噬在中医治疗AD过程中发挥着重要作用,文章总结近5年的实验研究,发现中医的多种干预手段均能够调控自噬及其信号通路,进而发挥治疗AD的作用。这些干预手段主要包括中药及其复方和针灸治疗。中药及其复方通过其多组分、多靶点的特性,能够针对AD的多个病理环节进行干预,既能够促进自噬的活性,清除异常蛋白的堆积,也能够抑制过度活跃的自噬,防止神经元自我损伤。针灸治疗则通过刺激穴位,调节神经系统的功能,影响自噬相关基因的表达和信号通路的活性,进而改善AD的病理状态。文章重点分析了中医手段如何调控自噬来防治阿尔茨海默病的现代病理机制,旨在从调控自噬的角度为临床改善AD提供新的研究方向和治疗靶点。

关键词：阿尔茨海默病自噬中医药研究进展针灸

Theoretical Study of the Effect of Multi-Diameter Distribution on the Mie Scattering Characteristics of Milk Fat

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Journal of Harbin Institute of Technology(New Series) 2015年第6期22卷 115-120页

作者： Jinying Yin siqi zhang Hongyan Yang Zhen Zhou School of Measurement and Communication Harbin University of Science & Technology

To correct the light scattering property parameters of milk fat for improving the detection accuracy,the Mie-theory was used to establish a predictive model for light scattering properties of milk fat globule with multi-diameter distributions, by means of Monte Carlo approach to simulate actual multi-diameter size distribution of milk fat globule in milk fat solution. Scattering coefficient and absorption coefficient of multidiameter distribution milk fat particles were calculated by simulating the particles size distribution in milk fat solution. And the light scattering properties of multi-diameter distribution was compared with that of volume mean diameter,Sauter mean diameter and numerical mean diameter in milk fat solution. Theoretical simulation results indicate that the scattering coefficient and absorption coefficient of milk fat particles are determined by the particle size distribution in milk fat solution. There is a distinct difference in scattering characteristics between the milk fat particles with multi-diameter distribution and that with mean diameters. Compared to that with multi-diameter distribution,the scattering coefficient of the milk fat particles with mean diameter has a maximum mean deviation of 9042 m-1. The particle size distribution is not completely determined by the mean diameters. The dependence of the light scattering properties on the particle size distribution should be considered into the model and simulation. Therefore,it is found that the particle size distribution in milk fat solution is an essential and critical factor to significantly improve the detection accuracy of milk fat content.

关键词： light scattering particle size distribution mie-theory milk fat globule

Biomarkers for neuromyelitis optica:a visual analysis of emerging research trends

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Neural Regeneration Research 2024年第12期19卷 2735-2749页

作者： Xiangjun Li Jiandong zhang siqi zhang Shengling Shi Yi’an Lu Ying Leng Chunyan Li Department of Ophthalmology Affiliated Hospital of Beihua UniversityJilinJilin ProvinceChina Department of Ophthalmology Changchun Bright Eye HospitalChangchunJilin ProvinceChina Departemt of Endocrinology Affiliated Hospital of Beihua UniversityJilinJilin ProvinceChina

Neuromyelitis optica is an inflammatory demyelinating disease of the central nervous system that differs from multiple *** the past 20 years,the search for biomarke rs for neuromyelitis optica has been ***,we used a bibliometric approach to analyze the main research focus in the field of biomarkers for neuromyelitis *** in this area is consistently increasing,with China and the United States leading the way on the number of studies *** Mayo Clinic is a highly reputable institution in the United States,and was identified as the most authoritative institution in this ***,Professor Wingerchuk from the Mayo Clinic was the most authoritative expe rt in this *** analysis revealed that the terms "neuro myelitis optica"(261 times), "multiple sclerosis"(220 times), "neuromyelitis optica spectrum disorder"(132 times), "aquaporin4"(99 times),and "optical neuritis"(87 times) were the most frequently used keywords in literature related to this *** analysis of the classical literature showed that the majority of publications provide conclusive research evidence supporting the use of aquaporin-4-IgG and neuromyelitis optica-IgG to effectively diagnose and differentiate neuromyelitis optica from multiple ***,aquaporin-4-IgG has emerged as a highly specific diagnostic biomarker for neuromyelitis optica spectrum *** oligodendrocyte glycoprotein-IgG is a diagnostic biomarke r for myelin oligodendrocyte glycoprotein antibody-associated *** biomarkers for neuromyelitis optica in clude cerebrospinal fluid immunological biomarkers such as glial fibrillary acidic protein,serum astrocyte damage biomarkers like FAM19A5,serum albumin,and gammaaminobutyric *** latest prospective clinical trials are exploring the potential of these *** results indicate that glial fibrillary acidic protein is emerging as a promising candidate biomarker for neuromyelit

关键词： aquaporin-4 autoantibody multiple sclerosis myelin oligodendrocyte glycoprotein antibody-associated disease neuromyelitis optica neuromyelitis optica spectrum disorder optical coherence tomography

On numerical earthquake prediction

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Earthquake Science 2014年第3期27卷 319-335页

作者： Yaolin Shi Bei zhang siqi zhang Huai zhang Laboratory of Computational Geodynamics of Chinese Academy of Sciences University of Chinese Academy of Sciences

Can earthquakes be predicted？ How should people overcome the difficulties encountered in the study of earthquake prediction？ This issue can take inspiration from the experiences of weather forecast. Although weather forecasting took a period of about half a century to advance from empirical to numerical forecast, it has achieved significant success. A consensus has been reached among the Chinese seismological community that earth- quake prediction must also develop from empirical fore- casting to physical prediction. However, it is seldom mentioned that physical prediction is characterized by quantitatively numerical predictions based on physical laws. This article discusses five key components for numerical earthquake prediction and their current status. We conclude that numerical earthquake prediction should now be put on the planning agenda and its roadmap designed, seismic stations should be deployed and observations made according to the needs of numerical prediction, and theoretical research should be carried out.

关键词： Earthquake prediction · Geodynamics ·Numerical method - Nonlinear dynamics

The effect of multiple pairs of meta-dicarboxyl groups on molecular self-assembly and the selective adsorption of coronene by hydrogen bonding and van der Waals forces

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Nano Research 2022年第2期15卷 1691-1697页

作者： Jianqiao Li Wendi Luo siqi zhang Chunyu Ma Xunwen Xiao Wubiao Duan Qingdao Zeng CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology(NCNST)Beijing 100190China Department of Chemistry School of ScienceBeijing Jiaotong UniversityBeijing 100044China School of Materials and Chemical Engineering Ningbo University of TechnologyNingbo 315211China

The prediction of two-dimensional molecular self-assembly structures has always been a problem to be *** molecules with meta-dicarboxyl groups can self-assemble into a specific hexagonal cavity,which has an important influence on the prediction of molecular self-assembly structures and the application of functional molecules with meta-dicarboxyl *** kinds of molecules with four pairs of meta-dicarboxyl groups,1,3,6,8-tet「akis(3,5-isophthalic acid)pyrene(H_(8)TIAPy)and 4′,4′",4′"",4""-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1′-biphenyl]-3,5-dicarboxylic acid))(H8ETTB)molecules were chosen to observe the self-assembly behavior at the heptanoic acid/highly oriented pyrolytic graphite(HA/HOPG)interface.H8TIAPy molecules self-assembled into well-ordered quadrilateral structures and could be regulated into kagome networks with hexagonal pores by coronene(COR)molecules.H8ETTB molecules self-assembled into lamellar structures and transformed into acid-COR-acid-COR co-assembled structures at low concentration of COR solution and acid-COR dimer-acid-COR dimer co-assembled structures at high concentration of COR *** reason that H8ETTB molecules could not be regulated into hexagonal porous architecture was attributed to the steric hindrance by the similar length and width of H8ETTB *** H8ETTB templates had stronger adsorption for COR than that of hexaphenylbenzene(HPB),regardless of the order of molecular introduction.

关键词： meta-dicarboxyl groups hexagonal cavity selective adsorption self-assembly steric hindrance