检索结果-南通市图书馆

Journal of Earth Science 2014年第1期25卷 1-44页

作者： yuri D Zakharov Alexander m Popov Far Eastern Geological Institute Far Eastern BranchRussian Academy of Sciences

After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in recovery, and their taxonomic diversity had not recovered to Late Permian levels even by the Olenekian. The differential patterns of recovery between these two clades may reflect fundamental differences in physiology and behavior. Brachiopods were benthic organisms that were dependent on specific trophic sources, and their general reduction in size during the Early Triassic may have been a response to a relative paucity of food resources. In contrast, ammonoids were sluggish- nektic organisms that utilized a wider range of trophic sources and that suffered no comparable size decrease during the Early Triassic. Brachiopods may have been at a disadvantage also due to vulner- abilities associated with their larval stage, during which they had to locate a suitable substrate for set- tlement. In contrast, ammonoids had no larval stage and juveniles may have been dispersed widely into favorable habitats. These factors may account for differences in the relative success of ammonoids and brachiopods at high-latitude regions following the End-Permian mass extinction： ammonoids success- fully reeolonized the Boreal region during the Early Triassic whereas brachiopods did not.

关键词： Lower Triassic South Primorye Kazakhstan brachiopod ammonoid biotic recovery.

Implementation of a Simulation model of the Controlled Release of molecular Species from Halloysite Nanotubes

在线全文

学校读者我要写书评

暂无评论

Journal of Encapsulation and Adsorption Sciences 2015年第1期5卷 74-92页

作者： Divya Narayan Elumalai yuri lvov Pedro Derosa Institute for micromanufacturing Louisiana Tech University Ruston LA USA Department of Physics Grambling State University Grambling LA USA

In this work a three-dimensional, time-quantified monte Carlo model that efficiently describes diffusion through and from nanotubes is implemented. Controlled delivery from Halloysite Nano-tubes (HNT) is modeled based on interactions between the HNT’s inner wall and the nanoparticles (NPs) and among NPs themselves. The model was validated using published experimental data. The validated model is then used to study the effect of multiples parameter like HNT diameter and length, particle charge, and ambient temperature on the release of encapsulated NPs. The results show that release profiles depend on the size distribution of the HNT batch used for the experiment, as delivery is sensitive to HNT lumen and length. A very good agreement with the experiment is observed when a weighted average release profile is compared to the experimental profile. Although the NP dynamics is temperature-dependent, the effect is minimum within the range of temperatures relevant to biomedical applications, but will be relevant for other applications at temperatures significantly different from room temperature. This model can be used to predict the best conditions for a particular delivery need.

关键词： Diffusion Controlled Release Halloysite Nanotubes montecarlo Sustained Release

Numerical investigation of full scale coaxial main rotor aerodynamics in hover and vertical descent

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2021年第5期34卷 666-683页

作者： Pavel V.mAKEEV yuri m.IGNATKIN Alexander I.SHOmOV Department of Helicopter Design Moscow Aviation Institute(National Research University)Moscow 125993Russia

The original free vortex wake model was used for numerical *** of the aerodynamic characteristics in hover and vertical descent modes in the range of vertical descent speed of 0–30 m/s including the Vortex Ring State(VRS)area was *** calculations were carried out under the condition of variable blade pitch angle values providing a fixed timeaverage thrust *** data of free vortex wake shapes,flow structures,and velocity fields were obtained and *** time-dependences of the rotor’s thrust and torque coefficients were obtained and *** obtained data allows determining the boundaries of the VRS area by various criteria such as rotor thrust and torque pulsations,growth of rotor power consumption relative to the hover,growth of rotor induced velocities relative to the hover,and growth of the required rotor blade pitch angles *** results of the study are compared with experimental and calculated data of other authors and can significantly supplement the available results of experimental and computational studies in this area.

关键词： Aerodynamic characteristics Coaxial rotor Free wake model Hover and vertical descent Vortex ring state mode

Approximations of the Fractional Integral and Numerical Solutions of Fractional Integral Equations

在线全文

学校读者我要写书评

暂无评论

Communications on Applied mathematics and Computation 2021年第3期3卷 545-569页

作者： yuri Dimitrov Department of mathematics and Physics University of Forestry1756 SofiaBulgaria Institute of mathematics and Informatics Bulgarian Academy of Sciences1113 SofiaBulgaria

In the present paper,we derive the asymptotic expansion formula for the trapezoidal approximation of the fractional *** use the expansion formula to obtain approximations for the fractional integral of ordersα,1+α,2+α,3+αand 4+α.The approximations are applied for computation of the numerical solutions of the ordinary fractional relaxation and the fractional oscillation equations expressed as fractional integral equations.

关键词： Fractional integral Trapezoidal approximation Fractional integral equation Finite-difference scheme

Phase-change composite filled natural nanotubes in hydrogel promote wound healing under photothermally triggered drug release

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bioactive materials 2023年第3期21卷 284-298页

作者： Jing-Jing Ye Long-Fei Li Rui-Nan Hao min Gong Tong Wang Jian Song Qing-Han meng Na-Na Zhao Fu-Jian Xu yuri lvov Li-Qun Zhang Jia-Jia Xue Beijing Laboratory of Biomedical materials State Key Laboratory of Organic-Inorganic CompositesBeijing University of Chemical TechnologyBeijing100029PR China College of materials Science and Engineering Beijing University of Chemical TechnologyBeijing100029PR China Beijing Laboratory of Biomedical materials Beijing University of Chemical TechnologyBeijing100029PR China Institute for micromanufacturing and Biomedical Engineering Program Louisiana Tech UniversityRustonLA71272USA

It is of great importance to treat a bacterial-infected wound by a smart dressing capable of delivering antibiotics in a smart manner without causing drug *** construction of smart release nanocontainers responsive to near-infrared(NIR)laser irradiation in an on-demand and stepwise way is a promising strategy for avoiding the emergence of multidrug-resistant ***,we develop a hydrogel composite made of alginate and nanotubes with an efficient NIR-triggered release of rifampicin and outstanding antibacterial *** composite hydrogel is prepared through co-encapsulating antibacterial drug(rifampicin),NIR-absorbing dye(indocyanine green),and phase-change materials(a eutectic mixture of fatty acids)into halloysite nanotubes,followed by incorporation into alginate hydrogels,allowing the in-situ gelation at room temperature and maintaining the integrity of drug-loaded *** them,the eutectic mixture with a melting point of 39℃ serves as the biocompatible phase-change material to facilitate the NIR-triggered drug *** resultant phase-change material gated-nanotubes exhibit a prominent photothermal efficiency with multistep drug release under laser *** an in vitro assay,composite hydrogel provides good antibacterial potency against Staphylococcus aureus,one of the most prevalent microorganisms of dangerous gas gangrene.A bacterial-infected rat full-thickness wound model demonstrates that the NIR-responsive composite hydrogel inhibits the bacteria colonization and suppresses the inflammatory response caused by bacteria,promoting angiogenesis and collagen deposition to accelerate wound *** NIR-responsive composite hydrogel has a great po-tential as an antibacterial wound dressing functionalized with controlled multistep treatment of the infected sites.

关键词： Anti-bacteria Clay nanotubes Alginate hydrogel Phase-change material NIR-Triggered drug release Infected wound healing

Nitrogen and Carbon Isotope Data of Olenekian to Anisian Deposits from Kamenushka/South Primorye, Far-Eastern Russia and Their Palaeoenvironmental Significance

维普期刊数据库评论

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 Earth Science 2018年第4期29卷 837-853页

作者： yuri D Zakharov micha Horacek Alexander m Popov Liana G Bondarenko Far Eastern Geological Institute of Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia BLT Wieselburg Research Center HBLFA Francisco-Josephinum Wieselburg 3250 Austria Institute of Lithospheric Research Vienna University Vienna 1090 Austria

The Kamenushka Formation, exposed in the northern part of South Primorye （Kamennshka-1 and Kamenushka-2 sections）, is one of the few localities in the world with richly fossiliferous Lower-Upper Olenekian sedimentary successions. Lower to middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete ^15Non- and ^13Corg- records for the Lower Triassic of this region. Nine N- isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the mesohedenstroemia bosphorensis Zone （upper part）, Shimanskyites shimanskyi and Neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the middle Spathian part of the Nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and majiashan sections.

关键词： Triassic N- and C-isotopes palaeoclimatology bio- and chemostratigraphy Pri- morye Russia.

mollisols Properties and Changes in Ukraine and China

在线全文

学校读者我要写书评

暂无评论

Chinese Geographical Science 2011年第3期21卷 257-266页

作者： yuri S KRAVCHENKO ZHANG Xingyi LIU Xiaobing SONG Chunyu Richard m CRUSE Key Laboratory of mollisols Agroecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China National University of Life and Environmental Sciences of Ukraine Kyiv 03041 Ukraine Department of Agronomy Iowa State University Ames 500011 IA USA

Soils are the foundation of civilizations and the basis for human food *** in Ukraine and Northeast China are two out of the four major mollisol regions in the *** natural areas from which mollisols developed are the prairies and steppes that experience temperate and freezing *** review paper introduces the general climate,vegetation,and topography of mollisols regions in Ukraine and Northeast China,analyzes their properties,including soil texture,soil organic matter content,soil bulk density,pH,cation exchange capacity and other chemical properties,and compares the property changes and management practices of mollisols in relation to sustainable grain production.

关键词： mollisols soil properties soil organic matter tillage mollisols management

Neurohumoral,cardiac and inflammatory markers in the evaluation of heart failure severity and progression

在线全文

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2021年第1期18卷 47-66页

作者： Ekaterina A Polyakova Evgeny N mikhaylov Dmitry L Sonin yuri V Cheburkin mikhail m Galagudza Almazov National medical Research Centre Saint-PetersburgRussia

Heart failure is common in adult population,accounting for substantial morbidity and mortality *** main risk factors for heart failure are coronary artery disease,hypertension,obesity,diabetes mellitus,chronic pulmonary diseases,family history of cardiovascular diseases,cardiotoxic *** main factor associated with poor outcome of these patients is constant progression of heart *** the current review we present evidence on the role of established and candidate neurohumoral biomarkers for heart failure progression management and diagnostics.A growing number of biomarkers have been proposed as potentially useful in heart failure patients,but not one of them still resembles the characteristics of the"ideal biomarker."A single marker will hardly perform well for screening,diagnostic,prognostic,and therapeutic management ***,the pathophysiological and clinical significance of biomarkers may depend on the presentation,stage,and severity of the *** authors cover main classification of heart failure phenotypes,based on the measurement of left ventricular ejection fraction,including heart failure with preserved ejection fraction,heart failure with reduced ejection fraction,and the recently proposed category heart failure with mid-range ejection *** could envisage specific sets of biomarker with different performances in heart failure progression with different left ventricular ejection fraction especially as concerns prediction of the future course of the disease and of left ventricular adverse/reverse *** article is intended to provide an overview of basic and additional mechanisms of heart failure progression will contribute to a more comprehensive knowledge of the disease pathogenesis.

关键词： cardiac and inflammatory markers in the evaluation of heart failure severity and progression Neurohumoral

Unique marine Olenekian-Anisian Boundary Section from South Primorye, Russian Far East

在线全文

学校读者我要写书评

暂无评论

Journal of China University of Geosciences 2005年第3期16卷 219-230页

作者： yuri D Zakharov Alexander m Popov Galina I Buryi Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 RussiaFar Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia

To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova）（dominant）, megaphyllites atlasoviensis Zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis Zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus Zakharov. Conodonts Neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.

关键词： South Primorye Triassic Olenekian-Anisian boundary ammonoid conodont