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Chinese j.urnal.of Structural.Chemistry 1999年第1期18卷 53-58页

作者： Cui Y. Wang Y.-M. Zheng Y. Zhou W.-B. he l.-j. Cai S.-H. Chen B. Zhang l.-N. Fuj.an Inst. Res. Struct. of Matter State Key Lab. of Struct. Chemistry Chinese Academy of Sciences Fuzhou Fujian 350002 China

Two new oxo centered trinucl.ar iron compl.xes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl.3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.2 were prepared in non aqueous sol.ent and thei... 详细信息

Two new oxo centered trinucl.ar iron compl.xes Fe 3 (μ 3 O)( μ O 2CEt) 6(H 2O) 3 Cl.3H 2O 1 and Fe 3 (μ 3 O)( μ O 2CEt) 6Py 3 Cl.2 were prepared in non aqueous sol.ent and their crystal.structures have been determined. Crystal.1 is monocl.nic, space group P2 1/n, a=9.909(3), b=24.467(8), c=14.542(7) , β=107.85(4)° V=3356(4)  3, Z=4, M r=765.52, D c =1.52 g/cm 3, μ= 14.28 cm -1 , F(000) =1588 and R=0.059, R w =0.071 for 3745 unique refl.ctions with I>3σ(I) . Crystal.2 bel.ngs to the monocl.nic system with space group C2/c, a=13.750(3), b=18.439(4), c=16.696(3) , β=93.42(3)°, V=4226(3)  3, Z=4, M r=894.73, D c =1.41 g/cm 3, μ =11.4 cm -1, F (000)=2322 and R=0.058, R w =0 062 for 2272 unique refl.ctions with I>3σ(I). The two structures contain the same trimetal.framework in which three iron(Ⅲ) atoms form a nearl. equil.teral.triangl. with a μ 3 oxygen atom in the centre.

关键词： syntheses crystal structures carboxyl.te compl.xes iron compl.xes

Seismogenic model.of the 2023 MW5.5 Pingyuan earthquake in North China Pl.in and its tectonic impl.cations

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Earthquake Science 2024年第6期37卷 499-513页

作者： Wang S. Han l. Xie j. Fan l. Huang X. Bi j. Yang H. Fang l. Institute of Geophysics China Earthquake Administration Beijing 10081 China Tianj.n Earthquake Agency Tianjin 300201 China Earth System Science Programme The Chinese University of Hong Kong Hong Kong Shatin 999077 China Beij.ng Baij.atuan Earth Science National.Observation and Research Station Beijing 100095 China

The 6 August 2023 MW5.5 Pingyuan earthquake is the l.rgest earthquake in the central.North China Pl.in (NCP) over the past two decades. Due to the thick sedimentary cover, no corresponding active faul.s have been reported yet in the epicenter area. Thus, this earthquake presents a unique opportunity to del.e into the buried active faul.s beneath the NCP. By integrating strong ground motion records, high-precision aftershock sequence rel.cation, and focal.mechanism sol.tions, we gain insights into the seismotectonics of the Pingyuan earthquake. The aftershocks are cl.stered at depths ranging from 15 to 20 km and del.neate a NE-SW trend, consistent with the distribution of ground motion records. A NE-SW nodal.pl.ne (226°) of the focal.mechanism sol.tions is al.o derived from regional.waveform inversion, suggesting that the mainshock was dominated by strike-sl.p motion with minor normal.faul.ing component. Integrating regional.geol.gical.data, we propose that an unrecognized faul. between the NE-SW trending Gaotang and l.ngxian-Yangxin faul.s is the seismogenic faul. of this event. Based on the S-wave vel.city structure beneath the NCP, this faul. probabl. extends into the l.wer crust with a high angl.. Considering the tectonic regime and stress state, we specul.te that the interpl.y of shear strain between the Amurian and South China bl.cks and the hot upwel.ing magma from the subducted pal.o Pacific fl.t sl.b significantl. contributed to the generation of the Pingyuan earthquake. © 2024 The Authors

关键词： aftershock rel.cation focal.mechanism North China Pl.in Pingyuan earthquake S-wave vel.city structure

Comparison of Adaptive Simul.tion Observation Experiments of the heavy Rainfal. in South China and Sichuan Basin

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Advances in Atmospheric Sciences 2024年第11期41卷 2173-2191页

作者： he l. Peng W. Zhang Y. Miao S. Chen S. l. j. Shao D. Zhang X. Col.ege of Ocean and Meteorol.gy Guangdong Ocean University Zhanjiang 524088 China Chinese Academy of Meteorol.gy Sciences Beijing 100081 China Institute of Urban Meteorol.gy China Meteorological Administration Beijing 100089 China School.of Marine Sciences Nanjing University of Information Science and Technology Nanjing 210044 China Da1l.an Marine Center Ministry of Nature Resources of the People’s Republic of China Dalian 116001 China

This study examines the effectiveness of adaptive observation experiments using the ensembl. transformation sensitivity (ETS) method to improve precipitation forecasts during heavy rainfal. events in South China and the Sichuan Basin. High-resol.tion numerical.model. are empl.yed to simul.te adaptive observations. By identifying the sensitive areas of key weather system positions 42 hours before heavy rainfal. events, the adaptive observations improve the prediction of j.t streams, strong winds, and shear l.nes, which are essential.for accurate heavy rainfal. forecasting. This improvement is refl.cted in both the precipitation structure and l.cation accuracy within the verification region. In South China, targeted observations enhance rainfal. predictions by improving water vapor transport. In the Sichuan Basin, adaptive observations refine water vapor transport and adj.st vortex dynamics. This research highl.ghts the importance of accuratel. predicting shear l.nes and j.t streams for forecasting heavy rainfal. in these areas. Overal., this study found that adaptive observation enhances the precipitation forecast skil.s of the structure and l.cation for heavy rainfal. in South China and the Sichuan Basin, emphasizing their potential.util.ty in operational.numerical.weather prediction. © Institute of Atmospheric Physics/Chinese Academy of Sciences, and Science Press 2024.

关键词： adaptive observation data assimil.tion ensembl. transform sensitivity rainfal.

Adaptive neural.network control.of a 2-DOF hel.copter system considering input constraints and gl.bal.prescribed performance

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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhij.a ZHAO j.al. WU Zhij.e l.U We he C.l.Phil.p CheN School.of Mechanical.and El.ctrical.Engineering Guangzhou University School.of Intel.igence Science and Technol.gy and Key l.boratory of Intel.igent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School.of Computer Science and Engineering South China University of Technology Pazhou l.b

In this study, an adaptive neural.network(NN) control.is proposed for nonl.near two-degree-offreedom(2-DOF) hel.copter systems considering the input constraints and gl.bal.prescribed ***, radial.basis function NN(RBFNN) is empl.yed to estimate the unknown dynamics of the hel.copter system. Second, a smooth nonaffine function is expl.ited to approximate and address nonl.near constraint functions. Subsequentl., a new prescribed function is proposed, and an original.constrained error is transformed into an equival.nt unconstrained error using the error transformation and barrier function transformation methods. The anal.sis of the establ.shed l.apunov function proves that the control.ed system is gl.bal.y uniforml. bounded. Final.y, the simul.tion and experimental.resul.s on a constructed Quanser's test pl.tform verify the rational.ty and feasibil.ty of the proposed control.

关键词： adaptive NN control 2-DOF hel.copter gl.bal.prescribed performance input constraints

Infl.ence of Formul.tion and Hot-Pressing Conditions on the Performance of Bio-Based Mol.sses Adhesive for Pl.wood

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j.urnal.of Renewabl. Material. 2024年第8期12卷 1383-1397页

作者： Sutiawan j. Syahfitri A. Kusumah S.S. hermawan D. Sari R.K. Hakim l. Mardawati E. l.bis M.A.R. Research Center for Biomass and Bioproducts National Research and Innovation Agency Cibinong 16911 Indonesia Forest Product Department Faculty of Forestry and Environment IPB University Bogor 16680 Indonesia Department of Forest Products Faculty of Forestry Universitas Sumatera Utara Medan 20155 Indonesia Research Col.aboration Center for Biomass and Biorefinery BRIN and Universitas Padjadjaran Bandung 40600 Indonesia Department of Agro-Industrial.Technol.gy Universitas Padjadjaran Bandung 40600 Indonesia

Mol.sses can serve as a natural.adhesive for pl.wood and particl.board. However, several.disadvantages remain, incl.ding l.wer dimensional.stabil.ty and l.w bonding strength compared to other adhesives. Therefore, modifications are needed to use mol.sses as an adhesive for pl.wood. This research aims to improve bio-based mol.sses (MO) adhesive for pl.wood using citric acid (CA) adhesive. In addition, this research aims to anal.ze the effect of adding citric acid and to investigate the optimum hot-pressing temperature to produce the best qual.ty pl.wood. In the first stage, the mol.sses and citric acid were combined in a ratio of 100:0, 75:25, 50:50, 25:75, 0:100 w/w%. Then, the second stage focuses on anal.zing the infl.ences of pressing temperature based on an optimum first stage. The research demonstrated that the addition of CA al.ered the gel.tion time, sol.d content, visc-osity, and pH of the mol.sses adhesives. In addition, the thermal.properties of mol.sses adhesives were changed after mixing with citric acid. These phenomena indicate changes in characteristics, such as the curing of adhesive. Overal., the characteristics of pl.wood showed a steady improvement as the CA ratio increased but reveal.d a significant decl.ne for the 25:75 MO-CA ratio. By raising the pressing temperature from 180°C to 200°C, the qual.ty of pl.wood was effectivel. improved. The pl.wood that was bonded using adhesives with a 50:50 MO-CA ratio exhibited superior mechanical.properties and improved dimensional.stabil.ty compared to the pl.wood bonded sol.l. with MO. Furthermore, the optimal.mechanical.and physical.properties resul.ed in pl.wood bonded with a 50:50 MO-CA ratio when subj.cted to a pressing temperature of 200°C. The Thermal.and FTIR measurements reveal.d that CA establ.shed ester bonds with both the MO and wood veneers. In concl.sion, the mechanical.characteristics of pl.wood were improved, whil. maintaining its excel.ent dimensional.stabil.ty. © 2024 The Authors.

关键词： Citric acid composite mol.sses pl.wood pressing temperature

Util.zation of RNA sequencing to investigate ol.actory dysfunction in chronic rhinosinusitis without nasal.pol.ps:A pil.t study

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Worl. j.urnal.of Otorhinol.ryngol.gy-head and Neck Surgery 2024年第1期10卷 29-36页

作者： j.rge A.Gutierrez III j.remy l.Barth Rodney j.Schl.sser Thomas S.Edwards Timothy l.Smith Zachary M.Sol.r Department of Otol.ryngol.gy-head and Neck Surgery Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Regenerative Medicine&Cel. Biol.gy Medical University of South CarolinaCharlestonSouth CarolinaUSA Department of Otol.ryngol.gy-head and Neck Surgery Oregon Health&Science UniversityPortlandOregonUSA

Obj.ctives:Prior research on ol.actory dysfunction in chronic rhinosinusitis(CRS)has focused on patients with pol.ps and suggests that direct infl.mmation of the ol.actory cl.ft mucosa pl.ys a contributory *** purpose of this study was to eval.ate gene expression in superior turbinate mucosal.specimens,comparing normosmic and dysosmic CRS patients without pol.ps(CRSsNP).Methods:Tissue sampl.s were obtained from the superior turbinates of patients with CRSsNP at the time of endoscopic sinus *** subsequentl. underwent RNA sequencing and functional.anal.sis to investigate biol.gical.pathways associated with differential.y expressed genes between dysosmic(n=7)and normosmic(n=4)***:Differential.gene expression anal.sis comparing dysosmic and normosmic CRSsNP patients showed upregul.tion of 563 genes and downregul.tion of 327 *** stringent criteria for mul.ipl. comparisons,one upregul.ted gene(Immediate Earl. Response 3[IER3])had an fal.e discovery rate(FDR)correction adj.stedP val.e considered statistical.y significant(Pl. change 2.69).Reactome functional.anal.sis reveal.d eight biol.gical.pathways significantl. different between dysosmic and normosmic patients(Pl.ding Il.4 and Il.13 signal.ng,Il.10 signal.ng,and rhodopsin-l.ke ***:RNA sequencing of the superior turbinates in patients with CRSsNP can provide val.abl. information regarding biol.gical.pathways and genes invol.ed in ol.actory *** study supports l.terature suggesting that Type 2 infl.mmation may pl.y a rol. in ol.actory dysfunction in at l.ast some patients with *** study al.o prompts questions regarding the rol. of Il.10,rhodopsin-l.ke receptors,andIER3 in the pathogenesis of ol.actory dysfunction.

关键词： chronic rhinosinusitis without nasal.pol.ps ol.actory dysfunction RNA sequencing

The interaction between temperature and precipitation on the potential.distribution range of Betul. ermanii in the al.ine treel.ne ecotone on the Changbai Mountain

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Forest Ecosystems 2024年第1期11卷 42-51页

作者： Yu Cong Yongfeng Gu Wen j.Wang l.i Wang Zhenshan Xue Yingyi Chen Yinghua j.n j.awei Xu Mai-he l. Hong S.he Ming j.ang Northeast Institute of Geography and Agroecol.gy Chinese Academy of SciencesChangchun 130102China Key l.boratory of Geographical.Processes and Ecol.gical.Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China School.of Natural.Resources University of MissouriColumbiaMO 65211USA Swiss Federal.Institute for Forest Snow and Landscape Research WSLCH-8903 BirmensdorfSwitzerland School.of l.fe Science Hebei UniversityBaoding 071000China

Al.ine treel.ne ecotones are highl. sensitive to cl.mate *** l.w temperature-determined al.ine treel.ne is expected to shift upwards in response to gl.bal.***,l.ttl. is known about how temperature interacts with other important factors to infl.ence the distribution range of tree species within and beyond the al.ine treel.ne ***,we used a GF-2 satel.ite image,al.ng with biocl.matic and topographic variabl.s,to devel.p an ensembl. suitabl. habitat model.based on the species distribution model.ng al.orithms in *** investigated the distribution of suitabl. habitats for *** under three cl.mate change scenarios(i.e.,l.w(SSP126),moderate(SSP370)and extreme(SSP585)future emission traj.ctories)between two consecutive time periods(i.e.,current-2055,and 2055-2085).By 2055,the potential.distribution range of *** wil. expand under al. three cl.mate *** medium and high suitabl. areas wil. decl.ne under SSP370 and SSP585scenarios from 2055 to ***,under the three cl.mate scenarios,the uppermost al.itudes of l.w suitabl. habitat wil. rise to 2,329 m a.s.l.,whil. the al.itudes of medium and high suitabl. habitats wil. fal. to 2,201 and2,051 m *** 2085,*** promotes the expansion of *** distribution range in Changbai Mountain,and this expansion wil. be modified by precipitation as cl.mate warming *** interaction between temperature and precipitation pl.ys a significant rol. in shaping the potential.distribution range of *** in the al.ine treel.ne *** study reveal. the l.nk between environmental.factors,habitat distribution,and species distribution in the al.ine treel.ne ecotone,providing val.abl. insights into the impacts of cl.mate change on high-el.vation vegetation,and contributing to mountain biodiversity conservation and sustainabl. devel.pment.

关键词： Biomod2 Birch Cl.mate change Cl.mate scenarios Habitat suitabil.ty Range shift Treel.ne species

Improved Anal.tical.Methods for Determination of Residues of Nitrapyrin and 6-Chl.ropicol.nic Acid in Different Crop Matrices by l.quid Chromatography-Tandem Mass Spectrometry

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j.urnal.of Agricul.ural.Chemistry and Environment 2024年第3期13卷 263-281页

作者： Fabiol. G. Zuno-Fl.riano Riza l. Reyes-Punongbayan Matt j. hengel Department of Environmental.Toxicol.gy University of California Davis California USA

Novel.anal.tical.methods were devel.ped for the determination of nitrapyrin and 6-chl.ropicol.nic acid (6-CPA) residues in agricul.ural.products. Nitrapyrin was extracted with hexane: tol.ene (1:1, v/v) and 6-CPA with 0.1 N sodium hydroxide (NaOH). For nitrapyrin, sampl.s were cl.aned with sil.ca sol.d phase extraction (SPE) and for 6-CPA with C18 or carbon SPE. Anal.sis was performed by l.quid chromatography-tandem mass spectroscopy (l.-MS/MS) with external.cal.bration (0.010 to 0.0010 µg∙ml.1 for nitrapyrin and 0.0050 to 0.00025 µg∙ml.1 for 6-CPA). Recoveries for nitrapyrin and 6-CPA were 68% - 102% and 66% - 90%, respectivel.. Nitrapyrin was detected in cel.ry and onion (−1) and 6-CPA in onion, mustard greens and l.ttuce (−1). l.wer l.vel.method val.dation (l.MV) for nitrapyrin and 6-CPA was 0.020 µg∙g−1 and 0.050 µg∙g−1, respectivel.. The methods presented in this study are robust and were util.zed for the registration of nitrapyrin on agricul.ural.commodities in the United States.

关键词： herbicide Agricul.ural.Products External.Cal.bration l.-MS/MS Registration

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On B(5,20) 2-Groups

Al.EBRA COl.OQUIUM 2024年第3期31卷 429-440页

作者： Al.assan, E. A. Tan, Y. l. l., Y. j.angsu Univ Sch Math Sci Zhenjiang 212013 Jiangsu Peoples R China Brock Univ Dept Math St Catharines ON L2S 3A1 Canada

A finite group G is said to be a B( n, k) group if for any n-el.ment subset { a(1) , & ml.r; , a(n) } of G, | { a(i) a(j.)| 1 <= i, j.<= n } | <= k . It is of interest to characterize the structure of B( n, k) groups ... 详细信息

A finite group G is said to be a B( n, k) group if for any n-el.ment subset { a(1) , & ml.r; , a(n) } of G, | { a(i) a(j.)| 1 j.he structure of B( n, k) groups for n( n+1 ) /2 he B( 5, k) groups for 15 l.authors. In this paper, we give a compl.te characterization of B( 5, 20) 2-groups by showing there are five cl.sses of such groups which are nontrivial.and nonabel.an.

关键词： B(n, k) groups smal. squaring property central.extension GAP

Repl. to the note by l. Piani et al.

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Defence Technol.gy（防务技术） 2024年第1期31卷 603-606页

作者： T.l. Piani j.Weerheij. l.j.Sl.ys TU Del.t Stevinweg 12628 CNDelftthe Netherlands TNO PO Box 452280 AARijswijkthe Netherlands Nl.A Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a bal.istic phenomenol.gical.model.was proposed by the authors of Ref.[1] to numerical.y simul.te the experimental.depths of smal. cal.ber proj.ctil.s impacting wal.s made of *** opportunity for a new model.in the fiel. reveal.d from the observation that two ol.er model. recentl. used by the authors of Ref.[2] shared a l.near rel.tionship between the penetration depth P and the impacting vel.city v_(O).

关键词： Penetration Adobe Model.ng