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Adaptive-optical 3D microscopy for microfluidic multiphase flows

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Light(Advanced Manufacturing) 2024年第3期5卷 105-119页

作者： Clemens Bilsing Erik Nützenadel Sebastian Burgmann jürgen Czarske Lars Büttner Laboratory of Measurement and Sensor System Techniques TUD Dresden University of Technology01069 DresdenGermany Chair of Fluid Mechanics Bergische Universitát Wuppertal42119 WuppertalGermany BIOLAS Laboratory of Measurement and Sensor System Techniques01069 DresdenGermany

Measurements based on optical microscopy can be severely impaired if the access exhibits variations of the refractive *** the case of fluctuating liquid-gas boundaries,refraction introduces dynamical aberrations that increase the measurement *** is prevalent at multiphase flows(***,film flows)that occur in many technical applications as for example in coating and cleaning processes and the water management in fuel *** this paper,we present a novel approach based on adaptive optics for correcting the dynamical aberrations in real time and thus reducing the measurement *** shape of the fluctuating water-air interface is sampled with a reflecting light beam(Fresnel Guide Star)and a Hartmann-Shack sensor which makes it possible to correct its influence with a deformable mirror in a closed ***-dimensional flow measurements are achieved by using a double-helix point spread *** measure the flow inside a sessile,oscillating 50-μl droplet on an opaque gas diffusion layer for fuel cells and show that the temporally varying refraction at the droplet surface causes a systematic underestimation of the flow field magnitude corresponding to the first droplet eigenmode which plays a major role in their detachment *** demonstrate that the adaptive optics correction is able to reduce this systematic ***,the adaptive optics system can pave the way to a deeper understanding of water droplet formation and detachment which can help to improve the efficiency of fuels cells.

关键词： Double-Helix point spread function Adaptive optics Particle tracking velocimetry Aberration correction Depth-resolving microscopy Closed-loop control

Endoscopic ultrasonography guided celiac plexus neurolysis and celiac plexus block in the management of pain due to pancreatic cancer and chronic pancreatitis

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World journal of Gastroenterology 2007年第26期13卷 3575-3580页

作者： Anthony j Michaels Peter v Draganov University of Florida Department of GastroenterologyHepatology and NutritionUnited States

Pain is a common symptom of pancreatic disease and is frequently difficult to manage. Pain relief provided by narcotics is often suboptimal and is associated with significant side effects. An alternative approach to pain management in pancreatic disease is the use of celiac plexus block (CPB) or neurolysis (CPN). Originally performed by anesthesiologists and radiologists via a posterior approach,recent advances in endoscopic ultrasonography (EUS) have made this technique an attractive alternative. EUS guided celiac plexus block/ neurolysis is simple to perform and avoids serious complications such as paraplegia or pneumothorax that are associated with the posterior approach. EUS guided CPN should be considered first line therapy in patients with pain due to pancreatic cancer. It provides superior pain control compared to traditional management with narcotics. A trend for improved survival in pancreatic cancer patients treated with CPN has been reported,but larger studies are needed to confirm this finding. At this time,the use of EUS guided CPB cannot be recommended as routine therapy for pain in chronic pancreatitis since only one-half of the patients experience pain reduction and the beneficial effect tends to be short lived. EUS guided CPB and CPN should be used as part of a multidisciplinary team approach for pain management.

关键词： Celiac plexus Celiac plexus neurolysis Celiacplexus block Endoscopic ultrasound Pain management

Colonoscopic polypectomy and associated techniques

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World journal of Gastroenterology 2010年第29期16卷 3630-3637页

作者： Christopher j Fyock Peter v Draganov Division of Gastroenterology Hepatology and NutritionUniversity of Florida

Polypectomy of colonic polyps has been shown to reduce the risk of colon cancer development and is considered a fundamental skill for all endoscopists who perform colonoscopy.A variety of polypectomy techniques and devices are available,and their use can vary greatly based on local availability and *** general,cold forceps and cold snare have been the polypectomy methods of choice for smaller polyps,and hot snare has been the method of choice for larger *** use of hot forceps has mostly fallen out of *** for difficult to remove polyps may require the use of special devices and advanced techniques and has continued to *** a result,the vast majority of polyps today can be removed *** electrocautery is frequently used for polypectomy,endoscopists should be thoroughly familiar with the basic principles of electrosurgery as it pertains to *** of a polypectomy site is an important adjunct to polypectomy and can greatly facilitate future surgery or endoscopic *** two most common post-polypectomy complications are bleeding and *** incidence can be decreased with the use of meticulous polypectomy techniques and the application of some prophylactic *** review will examine the technique of polypectomy and its complications from the perspective of the practicing gastroenterologist.

关键词： Colonic polyp Polypectomy Colonoscopy Polypectomy technique Complications

Growth and properties of semi-organic nonlinear optical crystal: L-Glutamic acid hydrochloride

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Progress in Natural Science:Materials International 2016年第1期26卷 24-31页

作者： j.Uma v.Rajendran Department of Physics Presidency College

Semiorganic nonlinear optical crystal of L-Glutamic acid hydrochloride（LGHC） was grown from aqueous solution by slow evaporation technique. Single crystal X-ray Diffraction analysis confirms that LGHC crystallizes in orthorhombic system with noncentrosymmetric space group P212121. The powder X-ray diffraction study confirms the crystallinity of the grown crystal. The fundamental functional groups of the grown crystals were analyzed by Fourier Transform Infrared spectroscopic analysis in the range of 450–4000 cm-1. The range of optical transmission was ascertained using Uv–vis–NIR studies. The Refractive Index of the LGHC crystal was found to be 1.4. The second harmonic generation efficiency of the LGHC was determined using Kurtz and Perry powder technique and it was 0.5 times greater than that of the KDP crystal. Thermo Gravimetric Analysis（TGA） and Differential Thermal Analysis（DTA） were used to study thermal behavior of the sample. The dielectric behavior and ac conductivity of the sample were studied as a function of frequency for different temperatures. The mechanical strength of the crystal was determined by vicker's Hardness test. The elastic stiffness constant and yield strength of the sample was calculated.

关键词： Semi organic nonlinear optical crystal X-Ray Diffraction Uv–vis–NIR Dielectric study Microhardness

Performance of inclined pillars with a major discontinuity

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International journal of Mining Science and Technology 2019年第3期29卷 437-443页

作者： K.v.j.ssu A.j.S.Spearing Western Australia School of Mines Kalgoorlie Curtin University

Discontinuities are an inherent part of the rock mass and majorly affect the stability of the excavation skin and *** dip of the discontinuities and their properties also have a significant effect on the strength of the *** approaches are commonly used to determine the pillar strength but can overestimate the strength and don’t consider the inclination of the pillars and the strength reduction caused by *** modeling is a powerful tool and if calibrated can be used to evaluate the strength of the pillars with discontinuities having a range of *** effect of a discontinuity on inclined pillars was conducted which has been seldom considered in evaluating the pillar ***-dimensional vertical pillars were simulated,and the pillar strength was calibrated to accepted theoretical results and then the discontinuities were introduced in different pillar inclinations with distinct width to height ratios to gain an insight into the effective pillar strength *** upon the results,it was found that the discontinuities have a significant effect with the increase in the inclination of the pillars even at a higher width to height ratios.

关键词： Numerical modelling Pillar Discontinuities Inclination Width to height ratios

Spectroscopic investigations on Yb^3+ doped and Pr^3+/Yb^3+ codoped tellurite glasses for photonic applications

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journal of Rare Earths 2021年第1期39卷 33-42,I0002页

作者： M.Seshadri M.j.v.Bell v.Anjos Y.Messaddeq Grupo de Engenharia e Espectroscopia de Materiais Departamento de Fisica-ICEUniversidade Federal de Juiz de ForaJuiz de ForaMG36036-900Brazil Centre d'Optique Photonique et Laser2375 Rue de la TerrasseUniversite LavalQuebecQCG1V 0A6Canada

In this work we repo rt on structural and spect roscopic properties of Yb^3+doped and Pr^3+/Yb^3+co-doped TeO2-Bi2 O3-ZnO-Li2 O-Nb2 O5(TBZLN)tellurite *** and stretching modes of TeO2 and Te-OH bond(strong and weak)were analysed from the deconvolution of observed Raman and FT-IR *** on the absorption measurements,the energy bands of Yb^3+and Pr^3+ions are *** spectroscopic properties for the radiative transitions of Yb^3+and Pr^3+ions were reported using McCumber and judd-Ofelt *** emission bands originating from 3 P1 and 3 P0 to lower lying levels of Pr^3+were registered under 447 nm *** emission band around 1334 nm assigned to the Pr3:1 G4→3 H5 was observed when excited at 980 *** stimulated emission cross-section(σemi(λ))and effective linewidth(Δλeff)for the 3 P1→3 H6,3 P1→3 H5,3 P0→3 H6,3 P0→3 F2,3 P1→3 F3,3 P1→3 F4,3 P0→3 F4 and 1 G4→3 H5 transitions of Pr^3+are *** luminescence in Pr^3+/Yb^3+codoped glass upon 980 nm excitation was *** resonant transfer processes between Yb^3+and Pr^3+ions are presented and *** chromaticity co-ordinates were also evaluated from the visible emission spectra showing that Pr^3+/Yb^3+co-doped glass may be suitable for the development of yellow-orange(λexc=447 nm)and near white light(λexc=980 nm)emitting devices in photonics.

关键词： Rare earth ions Tellurite glass Spectroscopic properties Upconversion luminescence

Simplicial Indicator Kriging

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journal of China University of Geosciences 2008年第1期19卷 65-71页

作者： R Tolosana-Delgado v Pawlowsky-Glahn j j Egozcue Department of Sedimentology and Environmental Geology Georg-August-Universitt Gttingen D-37077 Gttingen Germany Department of Computer Science and Applied Mathematics University of Girona Girona Spain Department of Applied Mathematics III Universidad Politécnica de Catalunya Barcelona Spain

Indicator kriging （IK） is a spatial interpolation technique devised for estimating a conditional cumulative distribution function at an unsampled location. The result is a discrete approximation, and its corresponding estimated probability density function can be viewed as a composition in the simplex. This fact suggested a compositional approach to IK which, by construction, avoids all its standard drawbacks （negative predictions, not-ordered or larger than one）. Here, a simple algorithm to develop the procedure is presented.

关键词： Aitchison geometry compositional data disjunctive kriging log-ratio approach simplex.

用于诊断肝细胞癌的肝脏影像报告及数据系统2018版5类：一项最新Meta分析

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国际医学放射学杂志 2024年第3期 373-374页

作者： S.Lee Y.Y.Kim j.Shin Y.H.Roh j.Y.Choi v.Chernyak 吴玉平

摘要目的该项更新的Meta分析旨在确定使用肝脏影像报告和数据系统（LI-RADS）2018版本（v2018）的LI-RADS LR-5类对肝细胞癌（HCC）的诊断能力，并通过评估成像方

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The influence of monomer concentration on the optical properties of electrochemically synthesized polypyrrole thin films

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journal of Semiconductors 2013年第10期34卷 13-18页

作者： j.v.Thombare M.C.Rath S.H.Han v.j.Fulari Holography and Material Research Laboratory Department of PhysicsShivaji UniversityKolhapur-416 004India Radiation and Photochemistry Division BARCMumbaiIndia Department of Chemistry Hanyang UniversitySeoulSouth Korea

Polypyrrole （PPy） thin films were deposited on stainless steel and ITO coated glass substrate at a constant deposition potential of 0.8 v versus saturated calomel electrode （SCE） by using the electrochemical polymerization method. The PPy thin films were deposited at room temperature at various monomer concentrations ranging from 0.1 M to 0.3 M pyrrole. The structural and optical properties of the polypyrrole thin films were investigated using an X-ray diffractometer （XRD）, FTIR spectroscopy, scanning electron microscopy （SEM）, and ultravioletvisible （Uv-vis） spectroscopy. The XRD results show that polypyrrole thin films have a semi crystalline structure. Higher monomer concentration results in a slight increase of crystallinity. The polypyrrole thin films deposited at higher monomer concentration exhibit high visible absorbance. The refractive indexes of the polypyrrole thin films are found to be in the range of 1 to 1.3 and vary with monomer concentration as well as wavelength. The extinction coefficient decreases slightly with monomer concentration. The electrochemically synthesized polypyrrole thin film shows optical band gap energy of 2.14 ev.

关键词： polypyrrole electrochemical polymerization method structure optical properties