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Synthetic and Systems Biotechnology 2023年第3期8卷 520-526页

作者： Zhijie Zhao Guiyun Zhao Yi Chai Wei Li kaihui song Wenbin Zhao Hairong Li Miaolian Wu Zhan Zhou Yi-Ling Du The Fourth Affiliated Hospital and Department of Microbiology School of MedicineZhejiang UniversityHangzhou310058China Yong Loo Lin School of Medicine National University of SingaporeSingapore Innovation Institute for Artificial Intelligence in Medicine College of Pharmaceutical SciencesZhejiang UniversityHangzhou310058China The Fourth Affiliated Hospital School of MedicineZhejiang UniversityYiwu322000China Zhejiang Provincial Key Laboratory for Microbial Biochemistry and Metabolic Engineering Hangzhou310058China

Microbial natural products have been one of the most important sources for drug *** the current postgenomic era,sequence-driven approaches for natural product discovery are becoming increasingly ***,we develop an effective genome mining strategy for the targeted discovery of microbial metabolites with antitumor *** method employs uvrA-like genes as genetic markers,which have been identified in the biosynthetic gene clusters(BGCs)of several chemotherapeutic drugs of microbial origin and confer self-resistance to the corresponding *** systematic genomic analysis of gifted actinobacteria genera,identification of uvrA-like gene-containing BGCs,and targeted isolation of products from a BGC prioritized for metabolic analysis,we identified a new tetracycline-type DNA intercalator *** results thus provide a new genome mining strategy for the efficient discovery of antitumor agents acting through DNA intercalation.

关键词： Genome mining Microbial natural product DNA intercalator UvrA-like protein Biosynthetic gene clusters Tetracycline

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水合肼在高岭石层间插层行为的量子化学研究

化学学报 2013年第11期71卷 1553-1562页

作者：张超王幸宋西亮宋开慧钱萍尹洪宗山东农业大学化学与材料科学学院泰安271018 山东省临沂市益民实验中学临沂276025

水合肼以其碱性及吸附性受到越来越多的关注,同时它在粘土中的污染问题也越来越受到重视.本工作构建了高岭石团簇模型为Al6Si6O42H42并在B3LYP/6-31G(d,p),MP2/6-31G(d,p)//B3LYP/6-31G(d,p)和MP2/6-31++G(d,p)//B3LYP/6-31G(d,p)水平下对一水合肼以及二水合肼在高岭石层间的插层性质(如:优化构型、结构参数、结合能、电荷分布、振动光谱、静电势等)进行探究.计算表明,当一水合肼进入层间后,水分子和肼分子之间的相互作用发生了改变.即水与肼分子分别以氢键的形式插层于高岭石层间,且肼与高岭石之间的相互作用要强于肼与水之间的相互作用,同时插层位点多位于高岭石四面体层和八面体层的重叠区域内,这些都是水合肼易进入高岭石层间而难以脱去的重要因素.当二水合肼进入层间后,随着层间距的不断扩大,肼分子与高岭石铝氧层之间的相互作用仍强于肼分子与水分子间的作用.但当层间距超过1.05 nm时,水分子与肼分子之间的作用则强于肼分子与高岭石的作用,这也印证了若要将肼脱附,需将层间距增大以减弱肼分子与高岭石的作用,再用溶剂将其脱附的可行性.

关键词：水合肼高岭石插层氢键

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term

模拟海洋大气环境下钛铝连接件的电偶腐蚀研究

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表面技术 2024年第9期53卷 11-21,I0005页

作者：董凯辉宋影伟蔡勇韩恩厚中国科学院金属研究所核用材料与安全评价重点实验室沈阳110016 中国科学技术大学材料科学与工程学院合肥230026 南方海洋科学与工程广东实验室(珠海) 广东珠海519000 广东腐蚀科学与技术创新研究院广州510530 华南理工大学材料科学与工程学院广州510641

目的探究海洋大气环境下飞机结构用钛铝连接件的电偶腐蚀行为,分析结构件各位置的电偶腐蚀差异,完善钛、铝金属间的电偶腐蚀机理。方法通过动电位极化曲线、零电阻电流(ZRA)及中性盐雾试验等,比较浸泡和薄液膜2种测试条件对腐蚀过程的... 详细信息

目的探究海洋大气环境下飞机结构用钛铝连接件的电偶腐蚀行为,分析结构件各位置的电偶腐蚀差异,完善钛、铝金属间的电偶腐蚀机理。方法通过动电位极化曲线、零电阻电流(ZRA)及中性盐雾试验等,比较浸泡和薄液膜2种测试条件对腐蚀过程的影响。利用有限元模拟(FEM)表征电偶作用在钛铝表面的影响范围,并预测各位置的腐蚀程度,最后通过腐蚀形貌和失重试验加以验证。结果在模拟海洋大气环境下钛及铝合金的阴极反应速率相较于浸泡条件下有所提高,耦合后两金属间的电偶电流密度由浸泡时的1.52μA/cm^(2)提升至11.00μA/cm^(2),腐蚀形态由局部点蚀凹坑转变为连续网格状腐蚀条纹。另外,钛与铝金属间的电偶电位(Eg=-700 mV,***)与阳极铝合金的自腐蚀电位(Ecorr,Al=-680 mV,***)接近,两者间较低的电位差使得电偶作用在铝表面的影响距离只有10~15 mm。结论钛铝连接件的电偶腐蚀主要集中在与钛直接接触的铝合金交界处,但不同边界位置的腐蚀深度也可能相差4倍以上,这主要与电偶作用影响范围内的阴/阳极面积比有关。

关键词：钛合金铝合金电偶腐蚀有限元模拟大气腐蚀薄液膜

Identification of Linear Systems Using Binary Sensors with Random Thresholds

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Journal of Systems Science & Complexity 2024年第3期37卷 907-923页

作者： HUANG Zhiyong song Qijiang School of Mathematics Renmin University of ChinaBeijing 100872China School of Mathematics Sino-French InstituteRenmin University of ChinaBeijing 100872China

In this paper,the problem of identifying autoregressive-moving-average systems under random threshold binary-valued output measurements is *** the help of stochastic approximation algorithms with expanding truncations,the authors give the recursive estimates for the parameters of both the linear system and the binary *** reasonable conditions,all constructed estimates are proved to be convergent to the true values with probability one,and the convergence rates are also established.A simulation example is provided to justify the theoretical results.

关键词： α-mixing binary sensor quantized system stochastic approximation stochastic thresh-old strongly consistent system identification

The learning curve for transurethral enucleation with bipolar energy for benign prostate hyperplasia:a single-surgeon experience of 494 patients

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Asian Journal of Andrology 2024年第3期26卷 288-294页

作者： Byeongdo song Sang Hun song Seong Jin Jeong Department of Urology Seoul National University Bundang HospitalSeongnam 13620Korea Department of Urology Seoul National University College of MedicineSeoul 03080Korea

This study was performed to investigate the learning curve of transurethral enucleation with bipolar energy(TUEB)for benignprostatic *** study involved 494 consecutive patients who underwent TUEB for benign prostatic hyperplasia fromAugust 2018 to March 2022 by one surgeon(SJJ,Seoul National University Bundang Hospital,Seongnam,Korea).The patientswere followed up at 1 week,1 month,3 months,and 6 months *** evaluate the learning curve of TUEB,perioperativeparameters including the enucleation ratio(enucleated tissue weight/transitional zone volume),TUEB efficiency(enucleatedtissue weight/operation time),and enucleation efficiency(enucleated tissue weight/enucleation time)were *** and postoperative complications were also assessed,including the International Prostate Symptom Score(IPSS),IPSSquality-of-life(QoL)score,and uroflowmetry *** patients’median age was 72(interquartile range[IQR]:66–78)years,and the estimated prostate volume and transitional zone volume were 63.0(IQR:46.0–90.6)ml and 37.1(IQR:24.0–60.0)ml,*** enucleation ratio,TUEB efficiency,and enucleation efficiency were 0.60(IQR:0.46–0.54)g ml−1,0.33(IQR:0.22–0.46)g min−1,and 0.50(IQR:0.35–0.72)g min−1,respectively,plateauing after 70 *** functional outcomes,including total IPSS,IPSS QoL score,and uroflowmetry outcomes,significantly improved at 6 months after TUEB(all P<0.05),but without significant differences over the learning ***-five(13.2%)patients developed complications after TUEB,21.5%of whom experienced major complications(Clavien–Dindo grade≥3).The rate of major complications declined as the number ofTUEB cases increased(P=0.013).Our results suggest that the efficiency of TUEB stabilized within 70 procedures.

关键词： benign prostate hyperplasia learning curve perioperative efficiency prostate transurethral enucleation with bipolar energy

Self-healing Ga-based liquid metal/alloy anodes for rechargeable batteries

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Nano Research 2024年第3期17卷 1366-1383页

作者： Meijia song Zhonghua Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212000China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJingshi Road 17923Jinan 250061China

With the rapid development of electronics,electric vehicles,and grid energy storage stations,higher requirements have been put forward for advanced secondary *** metal/alloy electrodes have been considered as a promising development direction to achieve excellent electrochemical performance in metal-ion batteries,due to their specific advantages including the excellent electrode kinetics and self-healing ability against microstructural electrode *** conventional liquid batteries,high temperatures are needed to keep electrode liquid and ensure the high conductivity of molten salt electrolytes,which also brings the corrosion and safety ***-based metal/alloys,which can be operated at or near room temperature,are potential candidates to circumvent the above *** this review,the properties and advantages of Ga-based metal/alloys are ***,Ga-based liquid metal/alloys as anodes in various metal-ion batteries are reviewed in terms of their self-healing ability,battery configurations,working mechanisms,and so ***,some views on the future development of Ga-based electrodes in batteries are provided.

关键词： metal-ion batteries Ga-based liquid metal/alloy anodes self-healing capability room temperature

A Novel Three-stage Tectonic Model for Mississippi Valleytype Zn-Pb Deposits in Orogenic Fold-and-Thrust Belts

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 843-849页

作者： song Yucai SinoProbe Laboratory Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China

Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons.

关键词： Mississippi Valley-type Zn-Pb deposits fold-and-thrust belts tectonic model structural or lithological traps extensional faults

Preparation and characterization of high-reactivity explosive-based nano-boron microspheres

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PARTICUOLOGY 2024年第10期93卷 125-136页

作者： Dong, Chen Wang, Yi Jia, Kanghui song, Dan song, Xiaolan An, Chongwei North Univ China Sch Mat Sci & Engn Taiyuan 030051 Peoples R China Jinxi Grp Shanxi Jiangyang Chem Co Ltd Taiyuan 030051 Peoples R China China Ordnance Inst Sci & Technol Beijing 100089 Peoples R China North Univ China Sch Environm & Safety Engn Taiyuan 030051 Peoples R China

Boron nanoparticles, with their remarkably high gravimetric and volumetric calorific values, emerge as the most promising fuel in energetic fields. However, challenges such as susceptibility to oxidation, high ignition temperature, and low combustion efficiency have constrained their further applications. In this study, we fabricated high explosives based nano-boron microspheres with uniform size using the electrostatic spray method, in which the boron nanoparticles and high explosives (CL-20 or PETN) are closely bonded together by fluorinated polymer (F-2602) and evenly distributed. The results indicated that the microspheres exhibited high sphericity and showed an enhanced antioxidant capability. The addition of high-energy explosives not only reduced the thermal oxidation temperature of nano-boron powder within the microspheres but also significantly enhanced the pressurization rate. Additionally, the microspheres with added high-energy explosives released more energy during the combustion process. Compared to physically mixed samples, electrostatically sprayed microspheres with a uniform microstructure still exhibited higher reactivity. Therefore, the design and synthesis of microspheres with controllable structures using the electrostatic spray method show promising application prospects. (c) 2024 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Nano-boron CL-20 PETN Electrospraying Ignition and combustion NANOPARTICLES COMBUSTION