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Variations of Atmospheric ELF/VLF Radio Noise Due to Seismogenic Modifications in Tropospheric Conductivity

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Open Journal of Earthquake Research 2024年第2期13卷 113-132页

作者： Masashi Hayakawa alexander P. Nickolaenko Hayakawa Institute of Seismo Electromagnetics Co. Ltd. (Hi-SEM) UEC Alliance Center #521 Tokyo Japan The University of Electro-Communications (UEC) Advanced Wireless & Communications Research Center (AWCC) Chofu-shi Tokyo O.ya. Usikov Institute for Radiophysics and Electronics National Academy of Sciences of the Ukraine Kharkov Ukraine

We suggest a possible explanation of the influence of pre-seismic activity on the registration rate of natural ELF(extremely low frequency)/VLF(very low frequency) pulses and the changes of their characteristics. The main idea is as follows. The distribution of the electric field around a thundercloud depends on the conductivity profile of the atmosphere. Quasi-static electric fields of a thundercloud decrease in those tropospheric regions where an increase of air conductivity is generated by pre-seismic activities due to emanation of radioactive gas and water into the lower atmosphere. The electric field becomes reduced in the lower troposphere, and the probability decreases of the cloud-to-ground (CG) strokes in such “contaminated” areas. Simultaneously, the electric field grows inside and above the thunderclouds, and hence, we anticipate a growth in the number of horizontal and tilted inter-cloud (or intra-cloud) (both termed as IC discharges) strokes. Spatial orientation of lightning strokes reduces vertical projection of their individual amplitudes, while the rate (median number strokes per a unit time) of discharges grows. We demonstrate that channel tilt of strokes modifies the spectral content of ELF/VLF radio noise and changes the rate of detected pulses during the earthquake preparation phase.

关键词： ELF/VLF Radio Noise Earthquake Precursor Pre-Seismic Modification Conductivity Anomaly in the Lower Atmosphere Radioactive Radon Gases CG Lightning Discharges IC Discharges Cloud-to-Ionosphere Discharge

The influence of composition of asphaltenes of different genesis on the properties of carbon materials manufactured from them by plasma processing

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Petroleum Science 2023年第6期20卷 3830-3840页

作者： Evgeniya Frantsina Yuliya Petrova Valentina Arkachenkova Andrey Grin'ko alexander pak Pavel Povalyaev Dmitry Zelentsov Kirill Cherednichenko Surgut State University Institute of Natural and Technical Sciencespr.Lenina 1628412SurgutRussian Federation Tomsk Polytechnic University Laboratory of Advanced Materials for the Energy Industrypr.Lenina30643050TomskRussian Federation National University of Oil and Gas Gubkin University Department of Physical and Colloidal Chemistrypr.Lenina65119991MoscowRussian Federation

The results of experimental studies of carbon materials, which are formed in the plasma of a direct current (DC) arc discharge initiated in open air from the asphaltenes of different origins, extracted from the natural asphaltite and from the oil of the Sredne-Ugutskoye Oilfield, are presented. The influence of the initial asphaltene composition on the composition and properties of the resulting carbon materials is analyzed. The initial asphaltenes and the samples of the carbon materials are characterized by the methods of X-ray diffraction, differential thermal analysis, X-ray fluorescence analysis, IR-Fourier spectroscopy, laser diffraction, transmission and scanning electron microscopy. The changes in the composition and structure of the asphaltenes are determined before and after their plasma treatment and the hypotheses are put forward concerning the chemical processes causing the changes in the molecular structure of the samples. As a result of plasma treatment of asphaltenes (100 A, 30 s), it was shown that graphitization occurs, as well as oxidation, and a decrease in sulfur content. Moreover, nanotubes and nano-onions have been detected using electron microscopy. Petroleum asphaltenes after plasma treatment give a less thermostable carbon material, but with a lower content of heteroatoms, and with a large amount of sulfur in the composition of sulfoxide structural fragments. This method is shown to be a promising technology for processing the petroleum feedstock enriched with heavy asphaltene components for the manufacture of carbon nanomaterials: nanotubes, nano-onions and polyhedral graphite.

关键词： Asphaltenes Natural asphaltite Carbon materials Nanomaterials Plasma treatment Graphite

Larch growth across thermal and moisture gradients in the Siberian Mountains

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Journal of Mountain Science 2023年第1期20卷 101-114页

作者： KHARUK Viacheslav I. PETROV Il'ya A. GOLYUKOV Alexey S. DVINSKAya Maria L. IM Sergei T. SHUSHPANOV alexander S. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041Russia Reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014Russia Tomsk State University Lenina str.36Tomsk634050Russia

Climate-driven changes in the thermal and moisture regimes may variously influence different tree species growth and *** hypothesize that drought resistant Siberian larch(Larix sibirica Ledeb.)and precipitation-sensitive Siberian pine(Pinus sibirica Du Tour)responded differently to climate change along the elevational thermal and precipitation *** studied the influence of air temperature,precipitation,soil moisture,and atmospheric drought(indicated by the drought index SPEI)on larch and pine growth along the southward megaslope of the West Sayan *** found that since 2000 climate change resulted in increasing larch and pine radial growth index(GI)(c.1.5–3times)within treeline(2000–2300 m)and timberline(1900–2000 m)ecotones,*** high precipitation *** the forest-steppe ecotone(1100–1200 m)in which *** is the only species,larch GI stagnated or even *** total forested area increased since 2000 up to+50%in the high elevations,whereas in the low elevations(<1400 m)area changes were *** treeline and timberline,trees’GI was stimulated by summer ***,temperature increase in early spring reduces GI due to living tissue activation followed by tissue damage by *** forest-steppe,larch radial growth was mostly dependent on soil *** shifted dependence on moisture to the early dates of the growing *** droughts decreased GI within forest-steppe as well as within treeline,whereas the drought influence on both species within highlands was *** forest-steppe seedlings establishment was poor,whereas it was successful within treeline and *** climate change leads to stagnation or even decrease in Larix sibirica growth in the southern lowland *** combination with poor seedlings establishment,reduced growth threatens the transformation of open lowland forests into forest-steppe and steppe ***,in the highlands warming

关键词： Larch Siberian pine Climate influence on tree radial growth Mountain forests Treeline Timberline Foreststeppe Drought stress Moisture stress

Tree clusters migration into alpine tundra,Siberia

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Journal of Mountain Science 2022年第12期19卷 3426-3440页

作者： KHARUK Viacheslav I. PETROV II'ya A. IM Sergei T. GOLYUKOV Alexey S. DVINSKAya Maria L. SHUSHPANOV alexander S. Sukacheu Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk 660036Russia Siberian Federal University Svobodny str.79Krasnoyarsk 660041Russia Reshetneu Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk 66014Russia Tomsk State University Leninastr.36Tomsk 634050Russia

We hypothesize that in mountain windy habitat trees formed clusters(hedges)as adaptive structures for seedlings’rooting,survival,and tress’upslope *** studied hedges formed by Siberian pine(Pinus sibirica du Tour)and larch(Larix sibirica Ledeb.)within the treeline ecotone in southern Siberian Mountains,investigated hedges formation,evolution,habitat amelioration,and analyzed tree’s growth index(GI)dependence on the eco-climate variables(air temperature,precipitation,soil moisture,wind speed)and relief features(elevation,aspect,slope steepness,and terrain curvature).We conducted a ground survey,measured biometrical parameters of trees and hedges,determined species composition and tree physiognomy,soil types and nutrient contents,and sampled wood cores and applied dendrochronology for trees’GI *** high-resolution satellite scenes for hedge detection and upslope migration,we found that winter winds and soil moisture are the main constraints of trees’settlement and *** formation always links with wind-sheltered microtopography features(boulders,local depressions or felled trees).Once the first tree is established,a positive feedback is aroused that facilitates seedling rooting and in-hedge habitat *** form a streamlined dense“common crown”that mitigates adverse winter wind *** always orient along the prevailing winds,and trees’uphill migration occurs by seedlings establishment within the leeward hedge *** growth facilitates soil formation and *** concentration of nutrients(K,P,N and S)within hedges exceeds the background by 1.5-5.5 *** extension leads to increased snow accumulation that mitigates the influence of desiccation and snow abrasion and mitigates seasonal water *** the extremely harsh windy habitat,inhedge trees present in mat,prostrate or krummholz *** warming,tree stems and even twigs turn *** that GI dependence on the wind speed is insignificant unt

关键词： Treeline Timberline Hedges Tree migration Siberian pine Larch Tree growth Siberian mountain forests Wind stress Moisture stress

Ballistic tests on hot-rolled Ti-6Al-4V plates:Experiments and numerical approaches

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Defence Technology（防务技术） 2023年第8期26卷 39-53页

作者： alexander Janda Benjamin James Ralph yael Demarty Marcel Sorger Stefan Ebenbauer Aude Prestl Ingo Siller Martin Stockinger Helmut Clemens Department of Materials Science Montanuniversitat LeobenFranz Josef-Straße 188700 LeobenAustria Department Product Engineering Montanuniversitat LeobenFranz Josef-Straße 188700 LeobenAustria French-German Research Institute of Saint-Louis 5 Rue du General Cassagnou68300 Saint-LouisFrance voestalpine BOEHLER Bleche GmbH&Co KG Boehler-Gasse 18680MürzzuschlagAustria

Superior ballistic performance and the lightweight character of Ti alloys are considered as main reasons for their use in armour applications against a broad spectrum of ballistic threats,***,fragment or blast *** dynamic loading caused by typical penetrators is characterized by high strain rates,only specific test methods allow a closer investigation of the respective material *** the present study,quasi-static and dynamic compression tests as well as ballistic tests were conducted on a twophase a+βalloy Ti-6Al-4V(in m%)manufactured by ***-deformation heat treatments,influencing microstructure and mechanical properties were applied in order to compare three different microstructural configurations:as-rolled,mill-annealed and ***,on the one hand,ballistic tests were employed for the determination of the ballistic limit velocity v_(50),compression tests,on the other hand,delivered essential input parameters for the application of the Johnson-Cook constitutive model in a finite element simulation of the impact *** comparison of experimental results to simulation results was supplemented by means of microstructural characterization of tested samples with the focus set on the prevalently observed deformation and damage mechanisms,as for example adiabatic shearing.

关键词： Ti-6Al-4V Ballistic performance Split Hopkinson pressure bar FE simulation Adiabatic shear bands Intermetallic phase

Four odontocete species change hearing levels when warned of impending loud sound

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Integrative Zoology 2018年第2期13卷 160-165页

作者： Paul E.NACHTIGALL alexander ya.SUPIN Aude F.PACINI Ronald A.KASTELEIN Hawaii Institute of Marine Biology University of HawaiiKaneohe HawaiiUSA Institute of Ecology and Evolution of the Russian Academy of Sciences MoscowRussia Sea Mammal Research Company(SEAMARCO) Harderwijkthe Netherlands

Hearing sensitivity change was investigated when a warning sound preceded a loud sound in the false killer whale(Pseudorca crassidens),the bottlenose dolphin(Tursiops truncatus),the beluga whale(Delphinaperus leucas)and the harbor porpoise(Phocoena phocoena).Hearing sensitivity was measured using pip-train test stimuli and auditory evoked potential *** the test/warning stimuli preceded a loud sound,hearing thresholds before the loud sound increased relative to the baseline by 13 to 17 *** with multiple frequencies of exposure and shift provided evidence of different amounts of hearing change depending on frequency,indicating that the hearing sensation level changes were not likely due to a simple stapedial reflex.

关键词： change dolphin hearing loud sound

Would integrated Western and traditional Chinese medicine have more benefits for stroke rehabilitation? A systematic review and meta-analysis

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Stroke & Vascular Neurology 2022年第1期7卷 77-85页

作者： Linda LD Zhong ya Zheng alexander Y Lau Norman Wong Liang yao Xingyao Wu Tengteng Shao Zhenxing Lu Huijuan Li Chun Sum Yuen Jianwen Guo Suzanne Lo Janita Chau Kam Wa Chan Bacon Fung Leung Ng Zhaoxiang Bian Edwin Chau-leung Yu Hong Kong Chinese Medicine Clinical Study Centre School of Chinese MedicineHong Kong Baptist UniversityHong Kong SARChina Department of Medicine and Therapeutics and Hong Kong Institute of Integrative Medicine Prince of Wales HospitalFaculty of MedicineThe Chinese University of Hong KongHong Kong SARChina Department of Health Research Methods Evidence and ImpactMcMaster UniversityHamiltonOntarioCanada Clinical Laboratory Shanghai Traditional Chinese Medicine Integrated Institute of Vascular AbnomaliesShanghaiChina Institute of Medical Research Northwestern Polytechnical UniversityXi'anShanxiChina Evidence Based Medicine Center School of Basic Medical SciencesLanzhou UniversityLanzhouChina School of Chinese medicine Hong Kong Baptist UniversityHong Kong SARChina Brain Center Guangdong Procincial Hospital of Traditional Chinese MedicineGuangdong University of Chinese MedicineGuangzhouChina The Nethersole School of Nuring Faculty of Medicinethe Chinese University of Hong KongHong Kong SARChina Department of Medicine Li Ka Shing Faculty of Medicinethe University of Hong KongHong Kong SARChina Department of Rehabilitation Sciences Hong Kong Polytechnic UniversityHong Kong SARChina Hong Kong Association for Integration of Chinese-Western Medicine Limited Hong Kong SARChina

Background Stroke is a major cause of death or long-term disability *** patients with stroke receive integrative therapy consisting of Western medicine(WM)and routine rehabilitation in conjunction with Chinese medicine(CM),such as acupuncture and Chinese herbal ***,there is no available evidence on the effectiveness of the combined use of WM and CM interventions in stroke *** The purpose of this meta-analysis is to evaluate the results of all individual studies to assess the combined use of CM and WM in stroke rehabilitation compared with WM *** The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were ***,EMBASE,Cochrane and China National Knowledge Infrastructure(CNKI)were *** included outcomes were dependency,motor function,depression and swallowing *** analysis was performed,and publication bias was assessed using funnel *** of review 58 studies and 6339 patients were included in the *** analysis revealed that combined therapy comprising both acupuncture and WM had a superior effect on improving dependency and swallowing function compared with standard WM therapy *** superiority of combined therapy comprising CM and WM in improving depression compared with standard WM therapy was also *** Our results indicate that the combined use of CM and WM could be more efficacious in stroke rehabilitation compared with the use of WM therapy ***,most studies were short in duration(2 to 4 weeks)and prone to different types of biases,which prevents making any conclusion regarding the long-term effects and raises concerns regarding true efficacy in context of high likelihood of Hawthorn ***,more randomised controlled trials with more rigorous design and longer duration of treatment and follow-up need to be conducted to compare WM alone versus WM and CM combined.

关键词： acupuncture routine alone

PHOTOSWITCHABLE NANOFLUOROPHORES FOR INNOVATIVE BIOIMAGING

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Journal of Innovative Optical Health Sciences 2011年第4期4卷 395-408页

作者： MING-QIANG ZHU GUO-FENG ZHANG CHONG LI ya-JING LI MATTHEW PALDRED alexander D.Q.LI Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China Department of Chemistry Washington State University PullmanWA 99164USA

Photosensitive fluorescent probes have become powerful tools in chemical biology and molecular biophysics,which are used to investigate cellular processes with high temporal and spatial ***,photosensitive fluorescent probes,including photoactivatable,photoconvertible,and photoswitchable fluorophores,have been extensively developed during the past *** photoswitchable fluorophores have received much attention because they highlight cellular events *** minireview summarizes recent advances of using reversibly photoswitchable fluorophores and their applications in innovative *** fluorophores include photoswitchable fluorescent proteins,photoswitchable fluorescent organic molecules(dyes),and photoswitchable fluorescent *** strategies have been developed to synthesize photoswitchable fluorophores,including engineering combination proteins,chemical synthesis,polymerization,and *** we concentrate on polymer nanoparticles with optically switchable emission properties:either fluorescence on/offor dualalternating-color fluorescence *** essential mechanisms of fluorescence photoswitching enable different types of photoswitchable fluorophores to change emission intensity or wavelength(color)and thus validating the basis of the fluorescence on/offor dual-color photoswitching *** the possible applications of any fluorophores are to label biological targets,followed by specific *** newly developed photoswitchable fluorophores enable super-resolution fluorescence imaging because of their photosensitive ***,we summarize the important area regarding future research and development on photoswitchable fluorescent nanoparticles.

关键词： Fluorescent molecular switches polymer nanoparticles two-photon two-photon imaging spiropyran

Characteristics of the active-layer under the China-Russia Crude Oil pipeline

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Journal of Mountain Science 2021年第2期18卷 323-337页

作者： SERBAN Mihaela LI Guo-yu SERBAN Raul-David WANG Fei FEDOROV alexander VERA Samsonova CAO ya-peng CHEN Peng-chao WANG Wei State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Da Xing’anling Observation and Research Station of Frozen-Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJiagedaqi 165000China University of Chinese Academy of Sciences Beijing 100049China Melnikov Permafrost Institute SB RASYakutsk 677010Russia PetroChina Pipeline Company Langfang 065000China Jiagedaqi Oil and Gas Transmission Sub-company PetroChina Pipeline CompanyJiagedaqi 165000China

Active layer is a key component for permafrost environment studies as many subsurface biological,biogeochemical,ecological,and pedogenic activities prevail in this *** study focuses on active layer temperature monitoring in an area with sporadic permafrost at two adjacent sites along China-Russia Crude Oil Pipeline(CRCOP),NorthEast *** T1 is located in disturbed ground on the right-of-way(on-ROW)2 m away from the center of the oil pipeline.T2 is located in a natural and undisturbed site,around 16.6 m *** objective was to study seasonal variability of the active layer depth and thermal regime from October 2017 to September *** monitoring sites consist of soil temperature probes arranged in a vertical array at different depths at both *** following parameters were computed:number of isothermal days(ID),freezing days(FD),thawing days(TD),freezing degree days(FDD),thawing degree days(TDD),number of freeze-thaw days(FTD).The mean air temperature in the monitoring period reached-3.2℃.The temperature profile indicates that the maximum active layer thickness observed during the study period was 10 m at T1 and 2 m at *** majority of the soil temperatures were above or close to 0℃,resulting in great values of TDD,especially in the first 4 m *** for T1 were predominant and ranged between 600-1160℃·days(0-4 m depth)reflecting the influence of oil temperature from the *** T2 borehole FDD were predominant for all the soil layer depths resulting in less permafrost *** comparison emphasizes the significant influence of vegetation removal and the dispersed heat from the pipeline on the active layer thickness.

关键词： Soil thermal regime Permafrost China Russia Crude Oil Pipeline Active layer