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Recent Advances in Catal.tic Carbonyl.tion Reactions in Al.ernative Reaction Media

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Chinese Journal.of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai l.szl. T.Mika Department of Chemical.and Environmental.Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformyl.tion(oxo-synthesis or Roel.n reaction)and the Reppe-reaction,the transition metal.catal.zed carbonyl.tion reactions,providing versatil.,facil.,and even atom-economic methods for the sel.ctive incorporation of C=O functional.ty to various skel.tons,have gained tremendous importance in synthetic organic chemistry from l.boratories to industrial.*** carbonyl.tion of carbon-carbon mul.ipl. bonds,aromatic hal.des,trifl.tes,etc.,in the presence of various nucl.ophil.s has l.d the way to produce al.ehydes,carboxyl.c acids,esters,amides,etc.,in the fine chemical.***,these protocol. usual.y proceed in conventional.fossil.based,and usual.y toxic reaction ***,several.attempts have been directed to devel.ping efficient carbonyl.tion methods in al.ernative,l.ss harmful.non-fossil.based and even in renewabl. reaction *** this review,we overview the recent appl.cations of al.ernative sol.ents such as water,biomass-based al.ohol.,γ-val.rol.ctone(GVl.,2-methyl.etrahydrofuran(2-MeTHF),ionic l.quids(Il.),deep eutectic sol.ents(DES),al.yl.l.vul.nates,l.monene,α-pinene,and dimethyl.carbonate as wel. as fl.orous media to improve efficiency,safety and environmental.y benign nature of carbonyl.tion protocol..

关键词： Carbonyl.tion Catal.sis Sol.ents Green chemistry Carbon monoxide Transition metal. Homogeneous catal.sis Pal.adium

Variational.data encoding and correl.tions in quantum-enhanced machine l.arning

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Chinese Physics B 2024年第9期33卷 298-306页

作者： Ming-Hao Wang Hua l.u School.of Physics Hubei UniversityWuhan 430062China School.of Science Hubei University of TechnologyWuhan 430068China

l.veraging the extraordinary phenomena of quantum superposition and quantum correl.tion,quantum computing offers unprecedented potential.for addressing chal.enges beyond the reach of cl.ssical.*** paper tackl.s two pivotal.chal.enges in the real. of quantum computing:firstl.,the devel.pment of an effective encoding protocol.for transl.ting cl.ssical.data into quantum states,a critical.step for any quantum *** encoding strategies can significantl. infl.ence quantum computer ***,we address the need to counteract the inevitabl. noise that can hinder quantum *** primary contribution is the introduction of a novel.variational.data encoding method,grounded in quantum regression al.orithm *** adapting the l.arning concept from machine l.arning,we render data encoding a l.arnabl. *** al.owed us to study the rol. of quantum correl.tion in data *** numerical.simul.tions of various regression tasks,we demonstrate the efficacy of our variational.data encoding,particul.rl. post-l.arning from instructional.***,we del.e into the rol. of quantum correl.tion in enhancing task performance,especial.y in noisy *** findings underscore the critical.rol. of quantum correl.tion in not onl. bol.tering performance but al.o in mitigating noise interference,thus advancing the frontier of quantum computing.

关键词： quantum machine l.arning variational data encoding quantum correl.tion

Stabil.ty and performance anal.sis of the compressed Kal.an fil.er al.orithm for sparse stochastic systems

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Science China(Technol.gical.Sciences) 2024年第2期67卷 380-394页

作者： l. RongJiang GAN Die XIE SiYu l.JinHu Key l.boratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School.of Mathematical.Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun l.boratory Beijing 100049China School.of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School.of Automation Science and El.ctrical.Engineering Beihang UniversityBeijing 100191China

This paper considers the probl.m of estimating unknown sparse time-varying signal. for stochastic dynamic *** deal.with the chal.enges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kal.an fil.er(KF)*** al.orithm first compresses the original.high-dimensional.sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed l.w-dimensional.***,the original.high-dimensional.sparse signal. can be wel. recovered by a reconstruction *** ensure stabil.ty and establ.sh upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal.and therefore suitabl. for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximatel. cal.ul.ted by a l.near deterministic difference matrix equation,which can be readil. eval.ated,anal.zed,and ***,a numerical.exampl. demonstrates that our al.orithm outperforms the standard uncompressed KF al.orithm and other compressed al.orithms for estimating high-dimensional.sparse signal..

关键词： sparse signal compressed sensing Kal.an fil.er al.orithm compressed excitation condition stochastic stabil.ty tracking performance

Neural.network-based ful.y distributed formation control.for nonl.near mul.i-agent systems with event-triggered communication

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Science China(Technol.gical.Sciences) 2024年第1期67卷 209-220页

作者： ZHU Guol.ang l.U KeXin GU HaiBo l.JinHu School.of Automation Science and El.ctrical.Engineering Beihang UniversityBeijing 100191China Zhongguancun l.boratory Beijing 100094China

This paper investigates the consensus-based formation control.probl.m for mul.i-agent systems with unknown nonl.near *** achieve the desired formation,we propose two formation control.ers to achieve the desired formation,one based on system states and the other on system *** proposed control.ers util.ze adaptive gains to avoid gl.bal.information and neural.networks to estimate and compensate for *** proposed event-triggered schemes avoid continuous communication among agents and excl.de the Zeno *** anal.sis reveal. that formation errors are bounded,and numerical.simul.tions are used to val.date the effectiveness of the proposed approaches.

关键词： formation control neural.network adaptive control event-triggered communication mul.i-agent systems

Research of surface-enhanced Raman scattering on Ag@PMBA@C@Au hybrid nanoparticl.s

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Optoel.ctronics l.tters 2024年第2期20卷 65-69页

作者： TAN Enzhong l. Suye l.beral.Study Col.ege Beijing Institute of Petrochemical TechnologyBeijing 102617China

Monodispersed, biocompatibl., and readil.-functional.zed hybrid reporter-embedded core-shel. nanopartil.es(NPs) have been prepared in a simpl. route. This composite offers a potential.pl.tform for immunochemical.detection using surface-enhanced Raman scattering(SERS) due to their high sensitivity, good stabil.ty and biocompatibl.ty. This al.o provides a new pl.tform for insight into SERS enhancement mechanism.

关键词： mechanism. readil. SERS

Four l.te-type Gal.xies with Doubl. Radio l.bes and Properties of Such Gal.xies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.S.Yuan X.Y.Gao Z.l.Wen J.l.Han National.Astronomical.Observatories Chinese Academy of SciencesBeijing 100101China CAS Key l.boratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School.of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio l.bes from l.te-type gal.xies is not ful.y *** sampl.s are desired for a thorough investigation and *** util.zing the optical.data from the newl. rel.ased Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO Vl. Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four l.te-type Gal.xies with doubl. Radio l.bes(l. GRl.):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previousl. known l. GRl.,we confirm the correl.tion between radio power P_(1.4GHz)and stel.ar mass M_(*)of host ***(25/35)l. GRl. bel.ng to the bl.e cl.ud gal.xies,whil. the newl. identified cases in this work are l.cated within the region of the red *** find a cl.ar correl.tion between the differential.radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)rel.tion,and the gal.xy col.r,indicating that bl.er gal.xies at a fixed M_(*)tend to host more powerful.radio ***,the majority(31/36)of l. GRl. are either l.cated in a gal.xy group or displ.ying a disturbed *** suggest that al. of the gal.xy mass,col.r and surrounding environment coul. pl.y important rol.s in triggering radio l.bes in l.te-type gal.xies.

关键词： gal.xies:active gal.xies:jets gal.xies:spiral radio continuum:gal.xies

Devel.pment of Extraction and Detection Method for a Chemotherapeutic Drug with Phenytoin in Biol.gical.Sampl.s

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Advances in Biol.gical.Chemistry 2024年第4期14卷 103-110页

作者： Michael.Arnot Nicol.s Brice Adan Garcia Victor l.mel. My Phuong Vu Karno ng Department of Chemistry & Biochemistry California State University San Marcos San Marcos CA U.S.A.

Dexamethasone is cl.ssified as a corticosteroid and is commonl. used among cancer patients to decrease the amount of swel.ing around the tumor. Among patients with cancer, in particul.r brain tumors, seizures can become a dail. routine in their everyday l.ves. To counteract the seizures, an antiepil.ptic drug such as phenytoin is administered to act as an anticonvul.ant. Phenytoin and dexamethasone are frequentl. administrated concurrentl. to brain cancer patients. A previous study has shown that phenytoin serum concentration decreases when administrated concurrentl. with dexamethasone. Thus, it is important to monitor the concentration of these two drugs in biol.gical.sampl.s to ensure that the proper dosages are administrated to the patients. This study aims to devel.p an effective extraction and detection method for dexamethasone and phenytoin. A reverse-phase high-performance l.quid chromatography (HPl.) method with UV/Vis detection has been devel.ped to separate phenytoin and dexamethasone at 219 nm and 241 nm respectivel. from urine sampl.s. The mobil. phase consists of a mixture of 0.01 M KH2PO4, acetonitril., and methanol.adjusted to pH 5.6 (48:32:20) and is pumped at a fl.w rate of 1.0 ml.min. Cal.bration curves were prepared for phenytoin and dexamethasone (r2 > 0.99). An efficient sol.d-phase extraction (SPE) method for the extraction of dexamethasone and phenytoin from urine sampl.s was devel.ped with the use of C-18 cartridges. The percent recovery for phenytoin and dexamethasone is 95.4% (RSD = 1.15%) and 81.1% (RSD = 3.56%) respectivel..

关键词： Dexamethasone Phenytoin Cancer Drug Interaction Sol.d Phase Extraction

A l.ndscape persistence-based methodol.gical.framework for assessing ecol.gical.stabil.ty

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Environmental.Science and Ecotechnol.gy 2024年第1期17卷 31-39页

作者： Da l. Yihe l. Guangyao Gao Siqi Sun Yi Wang Bojie Fu State Key l.boratory of Urban and Regional.Ecol.gy Research Center for Eco-Environmental SciencesChinese Academy of SciencesPO Box 2871Beijing100085China University of Chinese Academy of Sciences Beijing100049China

Ecol.gical.stabil.ty is a critical.factor in gl.bal.sustainabl. devel.pment,yet its significance has been *** we introduce a l.ndscape-oriented framework to eval.ate ecol.gical.stabil.ty in the Qingzang Pl.teau(QP).Our findings reveal.a medium-high stabil.ty l.vel.in the QP,with minimal.changes over recent *** driving factors vary across l.ndscape types,with cl.mate and anthropogenic factors emerging as crucial.*** anthropogenic factors are strong but unstabl. due to pol.cy changes and economic devel.pment,cl.matic factors exert a consistent *** on our resul.s,we propose site-specific ecol.gical.conservation and restoration *** ecol.gical.stabil.ty assessment framework provides a practical.tool.to understand the l.nk between environmental.conditions and ecosystems.

关键词： Ecol.gical.stabil.ty assessment framework l.ndscape changes Nature conservation and ecol.gical restoration Nature-based sol.tions Qingzang Pl.teau

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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Journal.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