检索结果-南通市图书馆

Chinese Journal of Aeronautics 2006年第B12期19卷 96-101页

作者： lu wan-bing YU wei WU Li-ping CUI Shuang-kui FU Guang-sheng College of Physics Science and Technology Hebei University Baoding 071002 China

Hydrogenated nanocrystalline silicon carbide （SIC） thin films were deposited on the single-crystal silicon substrate using the helicon wave plasma enhanced chemical vapor deposition （HW-PECVD） technique. The influences of magnetic field and hydrogen dilution ratio on the structures of SiC thin film were investigated with the atomic force microscopy （AFM）, the Fourier transform infrared absorption （FTIR） and the transmission electron microscopy （TEM）. The results indicate that the high plasma activity of the helicon wave mode proves to be a key factor to grow crystalline SiC thin films at a relative low substrate temperature. Also, the decrease in the grain sizes from the level of microcrystalline to that of nanocrystalline can be achieved by increasing the hydrogen dilution ratios. Transmission electron microscopy measurements reveal that the size of most nanocrystals in the film deposited under the higher hydrogen dilution ratios is smaller than the doubled Bohr radius of 3C-SiC （approximately 5.4 nm）, and the light emission measurements also show a strong blue photoluminescence at the room temperature, which is considered to be caused by the quantum confinement effect of small-sized SiC nanocrystals.

关键词： silicon carbide nanostructures plasma processing deposition

Emodin ameliorates lipopolysaccharides-induced corneal inflammation in rats

在线全文

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2015年第4期8卷 665-669页

作者： Guo-Ling Chen Jing-Jing Zhang Xin Kao lu-wan wei Zhi-Yu Liu Department of Ophthalmology the Second Hospital of Shandong University Department of Ophthalmology the Third People's Hospital of Jinan Department of Anatomy Shandong Univeristy School of Medicine

· AIM: To investigate the effect of emodin on pseudomonas aeruginosa lipopolysaccharides(LPS)-induced corneal inflammation in rats.· METHODS: Corneal infection was induced by pseudomonas aeruginosa LPS in Wistar rats. The inflammation induced by LPS were examined by slit lamp microscope and cytological checkup of aqueous *** tissue structure was observed by hematoxylin and eosin(HE) staining. The activation of nuclear factor kappa B(NF-κB) was determined by Western *** ribonucleic acid(m RNA) of tumor necrosis factor-α(TNF-α) and intercellular adhesion molecule-1(ICAM-1) in LPS-challenged rat corneas were measured with reverse transcription-polymerase chain reaction(RT-PCR).· RESULTS: Typical manifestations of acute corneal inflammation were observed in LPS-induce rat model,and the corneal inflammatory response and structure were improved in rats pretreated with emodin. Treatment with emodin could improve corneal structure, reduce corneal injure by reducing corneal inflammatory response. Emodin could inhibit the decreasing lever of inhibitor of kappa B alpha(IкBα) express, and the m RNA expression of TNF-α and ICAM-1 in corneal tissues was also inhibited by emodin. The differences were statistically significant between groups treated with emodin and those without treatment(P luSION: Emodin could ameliorate LPS-induced corneal inflammation, which might via inhibiting the activation of NF-κB.

关键词： nuclear factor kappa B inhibitor alpha therapy inflammation

Protective Effect of Emodin against Lipopolysaccharides-induced Corneal Injury in Rats

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 Medical Sciences Journal 2009年第4期24卷 236-240页

作者： Guo-ling Chen Zhi-yu Liu Jing wang Xue Gao lu-wan wei Yan-Li Liu Ophthalmic Center/Department of Ophthalmology Second Hospital Shandong University Jinan 250033 China Department of Anatomy School of Medicine Shandong University Jinan 250012 China

Objective To investigate the effect of emodin on lipopolysaccharides （LPS）-induced corneal injury in rats. Methods Three parallel incisions on the central surface of corneal epithelium were made and LPS was applied on them to induce corneal injury in Wistar rats. All rats were randomly divided into emodin group （n=40） and keratitis group （n=40）. Rats in the emodin group received subconjunctival injection of emodin and rats in the keratitis group received its vehicle 30 minutes before LPS exposure. At different time points-1 3, 6, 12, and 24 hours after LPS exposure, the symptoms of all rats were observed and the severity of their ocular inflammation was examined with a slit lamp microscope, then 8 rats in each group were killed through cervical dislocation and their eyes were enucleated and prepared to observe pathological changes of corneal tissue under a light microscope. The activation of nuclear factor-loB （NF-κB） under different condi- tions was determined by Western blot. Immunocytochemistry staining with an antibody against intercellular adhesion molecule-1 （ICAM-1） was performed to identify positive cells in corneal tissues. Results The model of acute keratitis was successfully established in Wistar rats. LPS could induce a typical corneal inflammatory response, such as hyperemia, corneal edema and opacity, which were observed in model rats. Compared with keratitis group, both ocular behaviors and damages of the corneal structure were improved in emodin group. Furthermore, the activation of NF-κB and the expression of ICAM-1 induced by LPS were markedly inhibited in emodin group. Conclusion Emodin can inhibit the activation of NF-κB and the expression of ICAM-I induced by LPS in corneas, protect against acute corneal injury, and improve symptoms in rats.

关键词： corneal, injury emodin lipopolysaccharides nuclear factor-κB

CBA: multi source fusion model for fast and intelligent target intention identification

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2024年第2期35卷 406-416页

作者： wan Shichang LI Qingshan wanG Xuhua lu Nanhua School of Computer Science and Technology Xidian UniversityXi’an 710071China School of Mathematics and Computer Application Shangluo UniversityShangluo 726000China

How to mine valuable information from massive multisource heterogeneous data and identify the intention of aerial targets is a major research focus at present. Aiming at the longterm dependence of air target intention recognition, this paper deeply explores the potential attribute features from the spatiotemporal sequence data of the target. First, we build an intelligent dynamic intention recognition framework, including a series of specific processes such as data source, data preprocessing,target space-time, convolutional neural networks-bidirectional gated recurrent unit-atteneion (CBA) model and intention recognition. Then, we analyze and reason the designed CBA model in detail. Finally, through comparison and analysis with other recognition model experiments, our proposed method can effectively improve the accuracy of air target intention recognition,and is of significance to the commanders’ operational command and situation prediction.

关键词： intention massive data deep network artificial intelligence

A Reliable Iteration Algorithm for One-Bit Compressive Sensing on the Unit Sphere

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第3期40卷 801-822页

作者： Yan-cheng lu Ning BI An-hua wan School of Mathematics Sun Yat-sen UniversityGuangzhou 510275China

The one-bit compressed sensing problem is of fundamental importance in many areas,such as wireless communication,statistics,and so ***,the optimization of one-bit problem coustrained on the unit sphere lacks an algorithm with rigorous mathematical proof of convergence and *** this paper,an iteration algorithm is established based on difference-of-convex algorithm for the one-bit compressed sensing problem constrained on the unit sphere,with iterating formula■,where C is the convex cone generated by the one-bit measurements andη_(1)>η_(2)>1/*** new algorithm is proved to converge as long as the initial point is on the unit sphere and accords with the measurements,and the convergence to the global minimum point of the l_(1)norm is discussed.

关键词： one-bit compressed sensing difference of convex algorithm iteration algorithm ■1-minimization

Exploring the impacts of major events on the systemic risk of the international energy market

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1444-1457页

作者： Ming-Tao Zhao Su-wan lu Lian-Biao Cui School of Statistics and Applied Mathematics Anhui University of Finance and EconomicsBengbu233030AnhuiChina Anhui Province Key Laboratory of Philosophy and Social Science of Low-Carbon Development and Carbon Finance Anhui University of Finance and EconomicsBengbu233030AnhuiChina

This study examines the systemic risk caused by major events in the international energy market(IEM)and proposes a management strategy to mitigate it. Using the tail-event driven network(TENET)method, this study constructed a tail-risk spillover network(TRSN) of IEM and simulated the dynamic spillover tail-risk process through the cascading failure mechanism. The study found that renewable energy markets contributed more to systemic risk during the Paris Agreement and the COVID-19pandemic, while fossil energy markets played a larger role during the Russia-Ukraine conflict. This study identifies systemically important markets(SM) and critical tail-risk spillover paths as potential sources of systemic risk. The research confirms that cutting off the IEM risk spillover path can greatly reduce systemic risk and the influence of SM. This study offers insights into the management of systemic risk in IEM and provides policy recommendations to reduce the impact of shock events.

关键词： International energy market Tail-risk spillover Cascading failure mechanism Systemic risk management

Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 1765-1779页

作者： Yan-Zhong Liang Bai-lu Teng wan-Jing luo School of Energy Resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： Lei wan Yizhou Tong Xi lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Icariin ameliorates viral myocarditis by inhibiting TLR4-mediated ferroptosis

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2024年第3期14卷 106-114,I0002-I0005页

作者： wei luo Yi lu Jun-Hua Deng Peng Liu Yan Huang wan-Xi Liu Chun-Li Huang Laboratory of the Atherosclerosis and Ischemic Cardiovascular Diseases Department of CardiologyAffiliated Hospital of Youjiang Medical University for NationalitiesYoujiang Medical University for NationalitiesBaiseGuangxi 533000China Department of Critical Care Medicine Affiliated Hospital of Youjiang Medical University for NationalitiesBaiseGuangxi 533000China Department of Respiratory and Critical Care Medicine Affiliated Hospital of Youjiang Medical University for NationalitiesBaiseGuangxi 533000China Postgraduate School of Youjiang Medical University for Nationalities BaiseGuangxi 533000China Department of Neonatology Affiliated Hospital of Youjiang Medical University for NationalitiesBaiseGuangxi 533000China Department of Nephrology People’s Hospital of PubeiQinzhouGuangxi 535300China Urban Community Health Service Center of Youjiang District BaiseGuangxi 533000China

Objective:To explore the mechanism by which icariin alleviates viral ***:CVB3-induced cardiomyocytes were used as an in vitro model of viral myocarditis to assess the effects of icariin treatment on cell viability,inflammation,and ***,the effects of icariin on ferroptosis and TLR4 signaling were *** AC16 cells were transfected with TLR4 overexpression plasmids,the role of TLR4 in mediating the regulatory effect of icariin in viral myocarditis was ***:Icariin significantly elevated cell viability and reduced inflammatory factors TNF-α,IL-1β,IL-6,and *** cytometry revealed that icariin decreased apoptosis rate,and the protein expression of Bax and cleaved caspase 3 and 9 in CVB3-induced ***,it suppressed ferroptosis including lipid peroxidation and ferrous ion,as well as the TLR4 ***,TLR4 overexpression abrogated the modulatory effects of ***:Icariin mitigates CVB3-induced myocardial injury by inhibiting TLR4-mediated *** animal study is needed to verify its efficacy.

关键词： Viral myocarditis CVB3 TLR4 Ferroptosis Icariin

Flow characteristics and bubble statistics during the fragmentation process of the ingested main cavity in plunging breaking waves

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 Hydrodynamics 2024年第3期36卷 546-555页

作者： Wen-bin Zhang wei-wen Zhao De-cheng wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

Plunging breaking waves play an important role in the exchange of heat,momentum,and mass between the atmosphere and *** this paper,a series of direct numerical simulations is conducted to investigate the fragmentation process of the ingested main cavity in plunging breaking *** two-phase Navier-Stokes equations are solved using the finite-volume method based on adaptive refinement *** free surface is captured using a geometrical volume of fluid *** 2-D,3-D simulations are *** flow fields at different stages of wave breaking are presented and quantitative analysis for bubbles is *** 2-D instantaneous vorticity field and local velocity field are visualized to discuss the general flow characteristics during the fragmentation *** a 2-D parametric study is conducted to investigate the differences in the flow characteristics during the fragmentation process under different wave parameters including initial wave steepness(ε),Bond number(Bo),and Reynolds number(Re).3-D vortex structures are shown to further investigate the mechanisms behind the differences in the flow *** bubble size distributions under two different initial wave steepness are also discussed with their relationship to the fragmentation process of the ingested main *** research offers a significant understanding of the distinct procedures and fundamental dynamics involved in wave breaking,enhancing our comprehension of this intricate event.

关键词： Plunging breaking waves multiphase flow bubble statistics