检索结果-南通市图书馆

Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry I.Nazarov Jorge Labella Alexey V.Kuzmin Maxim A.Faraonov Evgenii N.Ivanov Salavat S.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri V.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid institute of Solid-State Physics RAS 142432 Chernogolovka Research institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov institute of Solution Chemistry of the russian academy of sciences 153045 Ivanovo institute for Advanced Research in Chemical sciences Universidad Autonoma de Madrid28049 Madrid IMDEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing Li Xin-Hua Ma Shu-Wang Cui Hao-Kun Chen Tian-Lu Chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu Liu Mao-Yuan Liu Ye Liu Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin Li-Qiao Yin Heng-Yu Zhang Liang-Wei Zhang College of Physics Hebei Normal UniversityShijiazhuang 050024China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China TIANFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China Key Laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China institute for Nuclear Research of the russian academy of sciences Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow institute of Physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large High Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-particle physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of particle physics at higher *** electron and thermal neutron detector(EN-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** EN-Detector Array(ENDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of ENDA configuration,and obtain expectations on the ENDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO ENDA

An advanced theoretical approach to study super-multiperiod superlattices:theory vs experiments

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2024年第2期45卷 57-66页

作者： Alexander Sergeevich Dashkov Semyon Andreevich Khakhulin Dmitrii Alekseevich Shapran Gennadii Fedorovich Glinskii Nikita Andreevich Kostromin Alexander Leonidovich Vasiliev Sergey Nikolayevich Yakunin Oleg Sergeevich Komkov Evgeniy Viktorovich Pirogov Maxim Sergeevich Sobolev Leonid Ivanovich Goray Alexei Dmitrievich Bouravleuv Saint-Petersburg Electrotechnical University"LETI" Saint Petersburg197022Russian Federation Alferov Saint-Petersburg National Research Academic University of the russian academy of sciences Saint Petersburg194021RussiaFne deration Saint Petersburg Polytechnic University of Peter the Great Saint Petersburg195251Russian Federation Shubnikov institute of Crystallography of Federal Scientific Research Centre“Crystallography and Photonics” Russian Academy of SciencesMoscow119333Russian Federation National Research Center‘Kurchatov institute’ Moscow123182Russian Federation University associated with IA EAEC Saint Petersburg194044Russian Federation institute for Analytical Instrumentation Saint Petersburg198095Russian Federation Ioffe institute Saint Petersburg194021Russian Federation

A new theoretical method to study super-multiperiod superlattices has been *** method combines the precision of the 8-band kp-method with the flexibility of the shooting method and the Monte Carlo *** method was applied to examine the finest quality samples of super-multiperiod Al_(0.3)Ga_(0.7)As/GaAs superlattices grown by molecular beam *** express photoreflectance spectroscopy method was utilized to validate the proposed theoretical *** the first time,the accurate theoretical analysis of the energy band diagram of super-multiperiod superlattices with experimental verification has been *** proposed approach highly accurately determines transition peak positions and enables the calculation of the energy band diagram,transition energies,relaxation rates,and gain *** has achieved a remarkably low 5%error compared to the commonly used method,which typically results in a 25%error,and allowed to recover the superlattice *** retrieved intrinsic parameters of the samples aligned with XRD data and growth *** proposed method also accurately predicted the escape of the second energy level for quantum well thicknesses less than 5 nm,as was observed in photoreflectance *** new designs of THz light-emitting devices operating at room temperature were suggested by the developed method.

关键词： super-multiperiod superlattice photoreflectance spectroscopy Kane model kp-method energy band diagram light amplifiers

Heterocyclic Molecules Tethered Branched Polymers with Innate Immune Stimulating Activity

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第5期6卷 1278-1288页

作者： Jiayu Zhao Liping Liu Yibo Wang Zichao Huang Yu Zhang Ruirui Qiao Thomas P.Davis Zhaohui Tang Wantong Song Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026 Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 Jilin Biomedical Polymers Engineering Laboratory Changchun 130022 Australian institute of Bioengineering and Nanotechnology The University of QueenslandBrisbaneQueensland 4072

We report herein an interesting finding that heterocyclic molecules tethered branched polymers exhibit innate immune stimulating *** we conjugated a series of five-,six-,or seven-membered heterocyclic molecules to branched polyethylenimine(bPEI),over 70%of them could induce the secretion of interferon-β(IFN-β)from murine dendritic and human leukemia monocytic(DC2.4 and THP-1)cells through activating the stimulator of interferon genes(STING)*** further proved that this kind of innate stimulating activity was dependent on the macromolecular architecture as heterocyclic molecules tethered linear PEI(lPEI)or dendritic polyamidoamine(PAMAM)induced no or much less IFN-β***,we prepared a series of poly-L-lysine(PLL)-derivatives with different branches to tether with heterocyclic molecules and proved that this kind of bPEI-like structure was important in en hancing the binding affinity with STING proteins and for exhibiting innate stimulating activity.

关键词： bioactive materials polymers heterocycles branched structure immunity

Composition regulates dissolved organic matter adsorption onto iron (oxy)hydroxides and its competition with phosphate: Implications for organic carbon and phosphorus immobilization in lakes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental sciences 2024年第10期144卷 159-171页

作者： ShuaiLong Wen JingJing Liu YueHan Lu JiaRu Dai XiuLin Huang ShiLin An Erik Jeppesen ZhengWen Liu YingXun Du State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese academy of sciences Beijing 100049China Molecular Eco-Geochemistry(MEG)Laboratory Department of Geological SciencesThe University of Alabama2017th AveTuscaloosaAL 35485USA School of Environmental Science and Engineering Nanjing Tech UniversityNanjing 210008China School of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing 404020China Department of Ecoscience Aarhus UniversitySilkeborg 8600Denmark Sino-Danish Centre for Education and Research University of Chinese Academy of SciencesBeijing 101408China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and ImplementationMiddle East Technical UniversityAnkara 06800Turkey

Dissolved organicmatter(DOM)is a heterogeneous pool of compounds and exhibits diverse adsorption characteristics with or without phosphorous(P)*** impacts of these factors on the burial and mobilization of organic carbon and P in aquatic ecosystems remain *** this study,an algae-derived DOM(ADOM)and a commercially available humic acid(HA)with distinct compositions were assessed for their adsorption behaviors onto iron(oxy)hydroxides(FeOx),both in the absence and presence of *** contained less aromatics but more protein-like and highly unsaturated structures with oxygen compounds(HUSO)than *** adsorption capacity of FeOx was significantly greater for ADOM than for ***-like and HUSO compounds in ADOM and humic-like compounds and macromolecular aromatics in HA were preferentially adsorbed by ***,ADOM demonstrated a stronger inhibitory effect on phosphate adsorption than *** observation suggests that the substantial release of autochthonous ADOM by algae could elevate internal P loading and pose challenges for the restoration of restore eutrophic *** presence of phosphate suppressed the adsorption of protein-like compounds in ADOM onto FeOx,resulting in an increase in the relative abundance of protein-like compounds and a decrease in the relative abundance of humic-like compounds in post-adsorption *** contrast,phosphate exhibited no discernible impact on the compositional fractionation of ***,our results show the source-composition characters of DOM influence the immobilization of both DOM and P in aquatic ecosystems through adsorption *** preferential adsorption of proteinaceous compounds within ADOM and aromatics within HA highlights the potential for the attachment with FeOx to diminish the original source-specific signatures of DOM,thereby contributing to the shared DOM characteristics observed across diverse aquatic environments.

关键词： Algal dissolved organic matter Humic acid Adsorption Phosphate Fractionation FT-ICR MS

Hypoxia-inducible factor-1αin myocardial infarction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Cardiology 2024年第4期16卷 181-185页

作者： IvanaŠkrlec Sergey N Kolomeichuk Faculty of Dental Medicine and Health Josip Juraj Strossmayer University of OsijekOsijek 31000Croatia institute of Biology Karelia Research Center of Russian Academy of SciencesPetrozavodsk 185910Russia Laboratory for Genomics Proteomicsand MetabolomicsResearch Institute of Biomedicine and Biomedical TechnologiesTyumen State Medical UniversityTyumen 625023Russia

Hypoxia-inducible factor 1(HIF1)has a crucial function in the regulation of oxygen levels in mammalian cells,especially under hypoxic *** importance in cardiovascular diseases,particularly in cardiac ischemia,is because of its ability to alleviate cardiac *** oxygen-responsive subunit,HIF1α,plays a crucial role in this process,as it has been shown to have cardioprotective effects in myocardial infarction through regulating the expression of genes affecting cellular survival,angiogenesis,and ***,HIF1αexpression induced reperfusion in the ischemic skeletal muscle,and hypoxic skin wounds in diabetic animal models showed reduced HIF1α*** expression of HIF1αhas been shown to reduce apoptosis and oxidative stress in cardiomyocytes during acute myocardial *** variations in HIF1αhave also been found to correlate with altered responses to ischemic cardiovascular *** addition,a link has been established between the circadian rhythm and hypoxic molecular signaling pathways,with HIF1αfunctioning as an oxygen sensor and circadian genes such as period circadian regulator 2 responding to changes in *** editorial analyzes the relationship between HIF1αand the circadian rhythm and highlights its significance in myocardial adaptation to *** the changes in molecular signaling pathways associated with diseases,specifically cardiovascular diseases,provides the opportunity for innovative therapeutic interventions,especially in low-oxygen environments such as myocardial infarction.

关键词： Cardiovascular pathologies Circadian genes Hypoxia-inducible factor 1 Hypoxia Gene-gene interaction

Consideration of the influence of supports in modeling the electromagnetic fields of 25 kV traction networks under emergency conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Global Energy Interconnection 2024年第4期7卷 528-540页

作者： Konstantin Suslov Andrey Kryukov Ekaterina Voronina Pavel Ilyushin Department of Hydropower and Renewable Energy National Research UniversityMoscow Power Engineering InstituteMoscow 11250Russia Department of Power Supply and Electrical Engineering Irkutsk National Research Technical UniversityIrkutsk 664074Russia Department of Transport Electric Power Irkutsk State Transport UniversityIrkutsk 664074Russia Department of Research on the Relationship between Energy and the Economy Energy Research Institute of the Russian Academy of SciencesMoscow 117186Russia

Single-phase 25 kV traction networks of electrified alternating current(AC)railways create electromagnetic fields(EMFs)with significant levels of *** most intense magnetic fields occur when short circuits exist between the contact wire and rails or *** the short duration of exposure,they can adversely affect electronic devices and induce significant voltages in adjacent power lines,which is dangerous for operating *** numerous investigations have focused on modeling the EMF of traction networks and power lines,the challenge of determining the three-dimensional electromagnetic fields near metal supports during the flow of a short-circuit current through them is yet to be *** this case,the field has a complex spatial structure that significantly complicates the calculations of *** study proposes a methodology,algorithms,software,and digital models for determining the EMF in the described emergency *** the modeling process,the objects being studied were represented by segments of thin wires to analyze the distribution of the electric charge and calculate the intensities of the electric and magnetic *** approach was implemented in the Fazonord software,and the modeling results show a substantial increase in EMF levels close to the support,with a noticeable decrease in the levels as the distance from it *** procedure implemented in the commercial software Fazonord is universal and can be used to determine electromagnetic fields at any electrical power facility that includes live parts of limited *** on the proposed procedure,the EMF near the supports of overhead power lines and traction networks of various designs could be determined,the EMF levels at substations can be calculated,and the influence of metal structures located near traction networks,such as pedestrian crossings at railway stations,can be considered.

关键词： Power supply systems AC railways Emergency conditions Electromagnetic fields near supports Modeling Electromagnetic safety

Arctic Sea Ice Variations in the First Half of the 20th Century:A New Reconstruction Based on Hydrometeorological Data

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric sciences 2024年第8期41卷 1483-1495,1686-1693页

作者： Vladimir A.SEMENOV Tatiana A.ALDONINA Fei LI Noel Sebastian KEENLYSIDE Lin WANG A.M.Obukhov institute of Atmospheric Physics RAS Moscow 119017Russia institute of Geography RAS Moscow 119017Russia Geophysical institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway Nansen Environmental and Remote Sensing Center Bergen 5007Norway Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

The shrinking Arctic sea-ice area(SIA) in recent decades is a striking manifestation of the ongoing climate *** of the Arctic sea ice have been continuously observed by satellites since 1979, relatively well monitored since the 1950s, but are highly uncertain in the earlier period due to a lack of observations. Several reconstructions of the historical gridded sea-ice concentration(SIC) data were recently presented based on synthesized regional sea-ice observations or by applying a hybrid model–empirical approach. Here, we present an SIC reconstruction for the period1901–2019 based on established co-variability between SIC and surface air temperature, sea surface temperature, and sea level pressure patterns. The reconstructed sea-ice data for March and September are compared to the frequently used Had ISST1.1 and SIBT1850 datasets. Our reconstruction shows a large decrease in SIA from the 1920 to 1940 concurrent with the Early 20th Century Warming event in the Arctic. Such a negative SIA anomaly is absent in Had ISST1.1 data. The amplitude of the SIA anomaly reaches about 0.8 mln km^(2) in March and 1.5 mln km^(2) in September. The anomaly is about three times stronger than that in the SIBT1850 dataset. The larger decrease in SIA in September is largely due to the stronger SIC reduction in the western sector of the Arctic Ocean in the 70°–80°N latitudinal zone. Our reconstruction provides gridded monthly data that can be used as boundary conditions for atmospheric reanalyses and model experiments to study the Arctic climate for the first half of the 20th century.

关键词： Arctic sea ice Arctic climate early 20th century warming climate variability

Structural Properties of Ions and Polyelectrolytes in Aqueous Solutions under External Electric Fields:The Sign Effect

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第9期42卷 1341-1352,I0007页

作者： Cheng-Jiang Lin Jun-Jun Wang Yuan Jiang Shu-Li Chen Hong-Fei Li Wen-Han Zhao Qing-Rong Huang Chang-Ru Rong Xiao-Zheng Duan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China National Key Laboratory of Advanced Vehicle Integration and Control China FAW Group Co.Ltd.Changchun130013China State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200438China Department of Food Science Rutgers University65 Dudley RoadNew BrunswickNew Jersey08901USA

We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric *** focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these *** simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric *** work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems.

关键词： Polyelectrolyte Ions Aqueous solutions External electric fields Asymmetric dipole