检索结果-南通市图书馆

X Y Z particles at BABAR

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第6期34卷 644-649页

作者： E.Prencipe LAPP-laboratoire de Annecy de Physique de Particules

This paper intends to shortly summarize the recent results on Spectroscopy, published from the BABAR Collaboration. The BABAR experiment is a B-factory, at SLAC, where asymmetric energy beams of electron-positron are accelerated and collide at the energy in the center of mass of T（4S）. In 9 years of data taking, BABAR had collected 433 fb^-1 equivalent luminosity on-peak-data at the T（4S） energy, 30 fb^-1 data at the T（3S） energy, 15 fb^-1 data at the T（2S） energy, and a scan around T（4S） was done, collecting 25 pb^-1 every 5 MeV. Thanks to the high luminosity achieved, it is possible to perform high precision measurements, and spectroscopy studies. An update on the measurement of the state X（3872） will be given, as final result published by using the whole dataset available. Then, a new preliminary Y（4260） measurement is reported, and the study of the invariant mass J/ψπ^＋π^- in ISR events is shown, where no evidence of the state Y（4050） is highlighted. As conclusion, the results on the angular distribution analysis performed on the state Z（4430） are reported.

关键词： spectroscopy charmonium BABAR

Hemodynamic and antifibrotic effects of a selective liver nitric oxide donor V-PYRRO/NO in bile duct ligated rats

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2006年第41期12卷 6639-6645页

作者： Frédéric Moal Nary Veal Eric Vuillemin Eric Barrière Jianhua Wang Lionel Fizanne Frédéric Oberti Olivier Douay Yves Gallois Dominique Bonnefont-Rousselot Marie Christine Rousselet Paul Calès laboratoire HIFIH UPRES 3859 Université Angers France laboratoire de Biochimie Université Angers France INSERM U481 Hopital Beaujon Clichy France laboratoire de Biochimie Hopital de 1a Salpêtrière Paris France

AIM: To assess whether a liver specific nitric oxide (NO) donor (V-PYRRO/NO) would prevent the development of portal hypertension and liver fibrosis in rats with bile duct ligation (BDL). METHODS: Treatment (placebo or V-PYRRO/NO 0.53 μmol/kg per hour) was administered i.v. to rats 2 d before BDL (D-2) and maintained until the day of hemodynamic measurement (D26). Intra-hepatic NO level was estimated by measuring liver cGMP level. Effects of V-PYRRO/NO on liver fibrosis and lipid peroxidation were also assessed. RESULTS: Compared to placebo treatment, V-PYRRO/ NO improved splanchnic hemodynamics in BDL rats: portal pressure was significantly reduced by 27% (P < 0.0001) and collateral circulation development was almost completely blocked (splenorenal shunt blood flow by 74%, P = 0.007). Moreover, V-PYRRO/NO significantly prevented liver fibrosis development in BDL rats (by 30% in hepatic hydroxyproline content and 31% in the area of fibrosis, P < 0.0001 respectively), this effect being probably due to a decrease in lipid peroxidation by 44% in the hepatic malondialdehyde level (P = 0.007). Interestingly, we observed a significant and expected increase in liver cGMP, without any systemic hemodynamic effects (mean arterial pressure, vascular systemic resistance and cardiac output) in both sham- operated and BDL rats treated with V-PYRRO/NO. This result is in accordance with studies on V-PYRRO/NO metabolism showing a specific release of NO in the *** in BDL rats improved liver fibrosis and splanchnic hemodynamics without any noxious systemic hemo- dynamic effects.

关键词： Nitric oxide Portal hypertension Liver fibrosis Hemodynamics Rats

The Apollon 10 PW laser: experimental and theoretical investigation of the temporal characteristics

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

High Power Laser Science and Engineering 2016年第3期4卷 127-133页

作者： D.N.Papadopoulos J.P.Zou C.Le Blanc G.Chriaux P.Georges F.Druon G.Mennerat P.Ramirez L.Martin A.Frneaux A.Beluze N.Lebas P.Monot F.Mathieu P.Audebert laboratoire pour l'Utilisation des Lasers Intenses CNRSEcole Polytechnique laboratoire Charles Fabry UMR 8501 Institut d'OptiqueCNRS Univ Paris Sud CEA Iramis SPAM

The objective of the Apollon 10 PW project is the generation of 10 PW peak power pulses of 15 fs at 1 shot min^(-1). In this paper a brief update on the current status of the Apollon project is presented, followed by a more detailed presentation of our experimental and theoretical investigations of the temporal characteristics of the laser. More specifically the design considerations as well as the technological and physical limitations to achieve the intended pulse duration and contrast are discussed.

关键词： high intensity lasers spatiotemporal effects ultrafast lasers

Doppler Global Velocimeter-Development and Validation with Measurements in a Round Free Jet

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2009年第1期18卷 74-84页

作者： X.Ottavy S.Goguey J.Berthiau I.Trébinjac laboratoire de Mécanique des Fluides et d’Acoustique(LMFA)

Doppler global velocimetry （DGV） has already been shown to be an interesting technique capable of measuring the three components of velocity in a plane. A 1-component DGV system is currently under development at the LMFA, using a stabilized continuous wave （CW） argon ion laser for ermssion, lne receiver Ieatures only one camera for both signal and reference images and incorporates a DEF1 system to adjust the incident laser light frequency and its transmission coefficient on the iodine cell absorption line. A description of the whole system is presented and a validation with measurements of axial velocities at several positions in a round free jet is proposed.

关键词： laser anemometry Doppler shift iodine vapor absorption line filter DEFI system image processing.

Properties of n-type SnO_2 semiconductor prepared by spray ultrasonic technique for photovoltaic applications

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2015年第12期36卷 34-37页

作者： H.Bendjedidi A.Attaf H.Saidi M.S.Aida S.Semmari A.Bouhdjar Y.Benkhetta laboratoire de Physique des Couches Minces et Applications Université de Biskra laboratoire des Couches minces et Interfaces Université Mentouri

Transparent conducting n-type SnO2 semiconductor films were fabricated by employing an inexpensive, simplified spray ultrasonic technique using an ultrasonic generator at deferent substrate temperatures （300, 350, 400, 450 and 500 ℃）. The structural studies reveal that the SnO2 films are polycrystalline at 350,400, 450, 500 ℃ with preferential orientation along the （200） and （101） planes, and amorphous at 300 ℃. The crystallite size of the films was found to be in the range of 20.9-72.2 nm. The optical transmittance in the visible range and the optical band gap are 80% and 3.9 eV respectively. The films thicknesses were varied between 466 and 1840 nm. The resistivity was found between 1.6 and 4 × 10^-2 Ω.cm. This simplified ultrasonic spray technique may be considered as a promising alternative to a conventional spray for the massive production of economic SnO2 films for solar cells, sensors and opto-electronic applications.

关键词： tin oxide thin films spray ultrasonic structural properties optical properties

Numerical modeling of centrifuge cyclic lateral pile load experiments

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2009年第1期8卷 61-76页

作者： Nikos Gerolymos Sandra Escoffier George Gazetas Jacques Garnier Civil Engineering National Technical UniversityAthens Greece laboratoire Central des Ponts et Chaussées Nantes France Lecturer laboratoire Central des Ponts et Chaussées Nantes France

To gain insight into the inelastic behavior of piles, the response of a vertical pile embedded in dry sand and subjected to cyclic lateral loading was studied experimentally in centrifuge tests conducted in laboratoire Central des Ponts et Chaussees. Three types of cyclic loading were applied, two asymmetric and one symmetric with respect to the unloaded pile. An approximately square-root variation of soil stiffness with depth was obtained from indirect in-flight density measurements, laboratory tests on reconstituted samples, and well-established empirical correlations. The tests were simulated using a cyclic nonlinear Winkler spring model, which describes the full range of inelastic phenomena, including separation and re-attachment of the pile from and to the soil. The model consists of three mathematical expressions capable of reproducing a wide variety of monotonic and cyclic experimentalp-y curves. The physical meaning of key model parameters is graphically explained and related to soil behavior. Comparisons with the centrifuge test results demonstrate the general validity of the model and its ability to capture several features of pile-soil interaction, including： soil plastification at an early stage of loading, ＂pinching＂ behavior due to the formation of a relaxation zone around the upper part of the pile, and stiffness and strength changes due to cyclic loading. A comparison of the p-y curves derived from the test results and the proposed model, as well as those from the classical curves of Reese et al. （1974） for sand, is also presented.

关键词： centrifuge test Winkler model p-y curves cyclic loading pile-soil separation/gapping nonlinear response experimental validation

Pressure-broadened atomic Li(2s-2p) line perturbed by ground neon atoms in the spectral wings and core

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2017年第7期26卷 67-74页

作者： Sabri Bouchoucha Kamel Alioua Moncef Bouledroua Physics Department Badji Mokhtar University laboratoire de Physique de la Matière et du Rayonnement Chérif Messaidia University laboratoire de Physique des Rayonnements Badji Mokhtar University

Full quantum calculations are performed to investigate the broadening profiles of the atomic lithium Li（2s-2p） resonance line induced by interactions with ground Ne（2s^22p^6） perturbers in the spectral wings and core. The X^2Σ~＋, A^2Π,and B^2Σ~＋ potential-energy curves of the two first low lying Li Ne molecular states, as well as the corresponding transition dipole moments, are determined with ab initio methods based on the SA-CASSCF-MRCI calculations. The emission and absorption coefficients in the wavelength range 550-800 nm and the line-core width and shift are investigated theoretically for temperatures ranging from 130 K to 3000 K. Their temperature dependence is analyzed, and the obtained results are compared with the previous experimental measurements and theoretical works.

关键词： pressure broadening emission and absorption coefficients linewidth lineshift

Electron Backscattered Diffraction of Transgranular Crack Propagation in Soft Steel

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2007年第6期24卷 1759-1762页

作者： A. Boumaiza T. Baudin N. Rouag R. Penelle laboratoire Microstructures et Defauts Universit6 Mentouri Constantine Algdrie laboratoire de Physico-Chimie de l'Etat Solide UMR CNRS 8648 Paris-Sud Orsay France

We consider the crack propagation in a soft steel sheet during the formation. The drawability is considered in relation with the structural anisotropy, the mechanical behaviour is related to both the grain morphology and the texture. The structure heterogeneity could lead to the apparition of micro-cracks. The results show the texture effect on the crack propagation and on the crack arrest in soft steel during the formation. The EBSD technique allows to show that the adjustment of the grain orientation from the initial main component {111}（112） towards the deformation orientation {111}（110） incites a trans-granular crack through a grain with initial {111}（112） orientation in a globally ductile material. It is the presence of grains with {111}（110） orientation which permits the closing of micro-cracks.

关键词： INITIATION GROWTH

NH_3 Plasma Surface Treatments of Engineering Fluoropolymers: A Way to Enhance Adhesion of Ni or Cu Thin Films Deposited by Electroless Plating

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

材料热处理学报 2004年第05B期25卷 1092-1097页

作者： Maurice Romand Marlene Charbonnier Yves Goepfert laboratoire de Sciences et Ingenierie des Surfaces and Laboratoire de Sciences et Ingenierie des Surfaces andUMR 5180 des Sciences Analytiques Universite Claude Bernard - Lyon 1 69622 Villeurbanne Cedex France

This paper describes the electroless Ni or Cu plating of some fiuoropolymer substrates through a tin-free activation process. Materials subjected to surface metallization are commercial Teflon() FEP, Nafion(), ACLAR() and LaRCTM-CP1 thin films which have recently gained a large scientific and technological interest due to their excellent thermal, chemical, mechanical and dielectric properties. The original approach implemented in the present work involves: (i)the grafting of nitrogen-containing functionalities on the polymer surfaces through plasma treatments in ammonia, (ii) the direct catalysis of the so-modified surfaces via their immersion in a simple acidic PdCl2 solution (i.e. without using a prior surface sensitization in an acidic SnCl2 solution), and finally (iii) the electroless metallization itself. However, prior to the immersion in the industrial plating baths, the chemical reduction of the Pd+2 species (species covalently tethered on the nitrogen-containing groups) to metallic palladium (PdO) is shown to be a key factor in catalyzing the electroless deposition initiation. This is made by immersion in an hypophosphite (H2PO2-) solution. Wettability measurements and X-ray photoelectron spectroscopy (XPS) experiments are used to characterize every surface modification step of the developed process. A cross-hatch tape test was used to asses the adhesion strength of the electroless films that is shown qualitatively good. In addition, a fragmentation test was developed in combination with electrical measurements. Its use allows to distinguish different adhesion levels at the metal/polymer interface and to evidence the influence of some processing parameters.

关键词：镍化学镀层铜化学镀层等离子表面处理表面催化 XPS 剥离试验