检索结果-南通市图书馆

Retinal circulation and its role in macular disorders in patients without systemic disease

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3期8卷 585-589页

作者： Priyangshu chandra aditya Sudhalkar Souvik mandal Jay Chhablani Smt.Kanuri Santhamma Retina Vitreous Centre L.V.Prasad Eye Institute Kallam Anji Reddy Campus L.V.Prasad Marg Banjara Hills Hyderabad Andhra Pradesh500034 India

AIM: To determine whether retinal circulatory changes play a role in the pathogenesis of macular disorders in patients who are otherwise healthy. METHODS: Patients with macular disorders that required angiographic imaging were included in this prospective case series. After a complete ocular exam,fluorescein angiography was performed using a standardized technique on the HRA-II(Heidelberg Engineering, Heidelberg, Germany) with special focus on the posterior pole. Only patients with good quality images were included in the analysis. Circulatory parameters recorded included the arm-choroid time,choroid-retinal artery, and finally the retinal artery-vein time. Zonal asymmetry(between the upper and lower zones divided by a line passing through the centre of the fovea) in transit times, if any was also noted. Appropriate statistical analysis was done. Circulation times were compared with age matched historical controls. Changes in retinal dye transit times relative to historical age matched controls, if any, were noted and compared between various ***: A total of 156 eyes of 156 patients(120 males)were included in the study. Mean age: 49.14 ±14.93 *** disorders studied were age related degeneration,polypoidal vasculopathy, central serous chorioretinopathy(CSCR) and parafoveal telangiectasia. Delayed circulation time was noted in CSCR patients ***: CSCR patients appear to have delayed arterial filling, retinal circulatory disturbances do not seem to contribute to the pathogenesis of other macular disorders.

关键词： fluorescein angiography circulation parafoveal telangiectasia idiopathic polypoidal choroidal vasculopathy age-related macular degeneration central serous chorioretinopathy

Boundary layer flow and heat transfer of a Casson fluid past a symmetric porous wedge with surface heat flux

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 Physics B 2014年第4期23卷 390-395页

作者： Swati Mukhopadhyay Iswar chandra mandal Department of Mathematics The University of Burdwan

The aim of this paper is to investigate numerically the boundary layer forced convection flow of a Casson fluid past a symmetric porous wedge. Similarity transformations are used to convert the governing partial differential equations into ordinary ones. With the help of the shooting method, the reduced equations are then solved numerically. Comparisons are made with the previously published results in some special cases and they are found to be in excellent agreement with each other. The results obtained in this study are illustrated graphically and discussed in detail. The velocity is found to increase with an increasing Falkner-Skan exponent whereas the temperature decreases. With the rise of the Casson fluid parameter, the fluid velocity increases but the temperature is found to decrease in this case. Fluid velocity is suppressed with the increase of suction. The skin friction decreases with the increasing value of Casson fluid parameter. It is found that the temperature decreases as the Prandtl number increases and thermal boundary layer thickness decreases with the increasing value of Prandtl number. A significant finding of this investigation is that flow separation can be controlled by increasing the value of the Casson fluid parameter as well as by increasing the amount of suction.

关键词： symmetric wedge Casson fluid heat flux suction/blowing

Effect of size on momentum distribution of electrons around vacancies in NiO nanoparticles

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2015年第4期24卷 296-299页

作者： Anjan Das Atis chandra mandal P.M.G.Nambissan Department of Physics A.P.C.Roy Government College Department of Physics University of Burdwan Applied Nuclear Physics Division Saha Institute of Nuclear Physics

Very small nickel oxide nanoparticles were prepared by a sol-gel procedure using nickel nitrate hexahydrate and ammonium hydroxide as precursors. The particles are in the range of 5 nm-11 rim. The x-ray diffraction （XRD） crystallography and high resolution transmission electron microscopy （HRTEM） were employed to characterize the samples. They were found to be polycrystalline in nature and fcc （NaCl-type） in structure, with the lattice parameter varying with annealing temperature. HRTEM pictures show that the as-prepared samples are hexagonal in shape. Positron annihilation spectroscopy was used to investigate the Doppler-broadened spectra of the samples. The S and W parameters revealed that the chemical surroundings and momentum distribution of the vacancy clusters vary with crystallite size.

关键词： nanoparticles semiconductor defect cluster positron annihilation sol-gel

Extraction of locked-up coal by strengthening of rib pillars with FRP--A comparative study through numerical modelling

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2017年第2期27卷 261-267页

作者： Das Arka Jyoti mandal Prabhat Kumar Ghosh chandra Nath Sinha Amalendu CSIR-Central Institute of Mining and Fuel Research Dhanbad 826001India

In some of the coalfields in India, coal seams are only developed but no extraction of pillars is possible due to the presence of surface or sub-surface structures and also non-availability of stowing materials which leads to huge amounts of coal being locked-up underground. Spontaneous heating and fire, accumulation of poisonous gases, severe stability issues leading to unsafe workings and environmental hazards are the major problems associated with the developed coal pillars. So, there is a pressing need for a technology for the mining industry to extract the huge amount of coal locked-up under different constraints. In this study, the locked-up coal is proposed to be extracted by artificially strengthening the rib pillars. The detailed comparative study is carried out to know the increase of extraction percentage of locked-up coal by strengthening the rib pillars with FRP. Extraction methodology is designed and studied through numerical modelling for its stability analysis to evaluate its suitability of application in underground.

关键词： Locked-up coal Confined core Yield criterion Strengthened rib pillar Strain softening

Characterization,spectroscopic investigation of defects by positron annihilation,and possible application of synthesized PbO nanoparticles

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第2期30卷 400-407页

作者： Sk Irsad Ali Anjan Das Apoorva Agrawal Shubharaj Mukherjee Maudud Ahmed P M G Nambissan Samiran mandal Atis chandra mandal Department of Physics University of BurdwanGolapbagBurdwan 713104West BengalIndia Department of Physics A.P.C.Roy Government CollegeSiliguriDarjeeling 734010West BengalIndia Applied Nuclear Physics Division Saha Institute of Nuclear Physics1/AF BidhannagarKolkata 700064India Department of Physics Government General Degree College at PedongKalimpong 734311West BengalIndia

Nanocrystalline samples of highly pure lead oxide were prepared by the sol-gel route of synthesis.X-ray diffraction and transmission electron microscopic techniques confirmed the nanocrystallinity of the samples,and the average sizes of the crystallites were found within 20 nm to 35 *** nanocrystallites exhibited specific anomalous properties,among which a prominent one is the increased lattice parameters and unit cell *** optical band gaps also increased when the nanocrystallites became smaller in *** latter aspect is attributable to the onset of quantum confinement effects,as seen in a few other metal oxide *** annihilation was employed to study the vacancy type defects,which were abundant in the samples and played crucial roles in modulating their *** defect concentrations were significantly larger in the samples of smaller crystallite *** results suggested the feasibility of tailoring the properties of lead oxide nanocrystallites for technological applications,such as using lead oxide nanoparticles in batteries for better performance in discharge rate and *** also provided the physical insight into the structural build-up process when crystallites were formed with a finite number of atoms,whose distributions were governed by the site stabilization energy.

关键词： lead oxide nanocrystals positron annihilation sol-gel processes

Larvicidal activity of Dregea volubilis and Bombax malabaricum leaf extracts against the filarial vector Culex quinquefasciatus

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2011年第6期4卷 436-441页

作者： Emdad Hossain Anjali Rawani Goutam chandra Subhash C.mandal Jayanta Kumar Gupta Pharmacy College AzamgarhItauraPO:ChandeshwarAzamgarh 276128Uttar PradeshIndia Department of Zoology Mosquito Research UnitParasitology LaboratoryThe University of BurdwanBurdwan 713104West BengalIndia Department of Pharmaceutical Technology Jadavpur UniversityKolkata 700032India

Objective:To analyze the larvicidal activity of two plant leaf powder and leaf-extracts, Dregea volubilis and Bombax malabaricum against Culex ***:The larvicidal bioassay was done for powdered leaves of Dregea volubilis and Bombax malabaricum individually and their methanol extracts against first-,second-,third- and fourth-instar larval forms of Culex *** rate was recorded after 24,48 and 72 h of postexposure. LC50 and LG90 values were calculated at different time intervals for third instar larvae. Results:All the graded concentration（0.1%,0.2%,0.3%,0.4%,0.5%） of powdered leaves showed significant（P 50 values were 56.97 ppm and 48.85 ppm,respectively after 24 h of *** is no mortality of non-target organism such as Chironomous circumdatus,Oreochromis niloticus niloticus and Diplonichus annulatum within 72 h of post exposure to 0.1%,0.2%,0.3%crude powdered leaves and methanolic extracts of both the two individual plants under the laboratory *** results of preliminary qualitative phytochemical analysis of both the plants revealed the presence of many bioactive principles such as steroids,tannins,flavonoids,triterpenoids,saponins,etc. that may be responsible for their bio-control ***:The results have shown potential and eco-friendly use of both plant extracts against larva of Culex quinquefasciatus for the first time.

关键词： Bombax malabaricum Culex quinquefasciatus Dregea volubilis Larvicidal activity

Bidirectional carrier aggregation in next-generation radio-over-fiber heterogeneous network based on FBMC

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 Optics Letters 2019年第6期17卷 11-15页

作者： Gour chandra mandal Rahul Mukherjee Khaleda Mallick Paulomi mandal Ardhendu Sekhar Patra Department of Physics Sidho-Kanho-Birsha University

We have projected and verified a bidirectional intra-/inter-radio-access-technology carrier-aggregation method for a next-generation heterogeneous mobile network supported by filter bank multicarrier(FBMC).Successful transmission of intra/inter-band carrier aggregation between five broadband FBMC signals and three bands 4G long-term-evolution-advanced signal over 50 km single-mode fiber plus 10 m free-space is successfully broadcasted by employing an incoherent light-injection scheme in *** uplink,two intra-bands carrier-aggregated wireless local area network Institute of Electrical and Electronics Engineers 802.11 g signal is carried over the equal *** receiver sensitivity,low error vector magnitude,and clear constellation diagrams show successful delivery of different wireless services for different ***,the proposed hybrid system should become a potential solution for a future mobile front-haul network because of its low latency and high capacity.

关键词： have projected and verified radio-access-technology proposed hybrid system

Ion Conduction in Superionic Glassy Electrolytes:An Overview

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2013年第3期29卷 193-208页

作者： Angesh chandra Alok Bhatt Archana chandra Department of Applied Physics Shri Shankaracharya Institute of Prof.Manag.& Tech.Raipur 492015C.G.India Department of Applied Physics M.P Christian College of Engg.& Tech.Bhilai 490026C.G.India

The various theoretical and experimental models for ion conduction mechanism of fast ion conducting （FIC） glass electrolytes have been reported in the present review paper. Some characterization techniques of FIC glasses are presented. The experimental methods for determination of some ion transport parameters viz ionic conductivity （σ）, ionic mobility （μ）, mobile ion concentration （n）, ionic drift velocity （Vd）, ionic transference number （tion） and activation energies of FIC glasses are explained. The solid state battery fabrication by using some FIC glasses is also reported.

关键词： Ion conduction Glassy solid electrolyte Fast ion conducting (FIC) glass Superionic solid Relaxation phenomenon

PEO-PVP BLENDED Na^+ION CONDUCTING SOLID POLYMERIC MEMBRANES

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2013年第11期31卷 1538-1545页

作者： Angesh chandra Department of Applied Physics Shri Shankaracharya Institute of Professional Management & Technology

Polyethylene oxide （PEO）-polyvinylpyrrolidone （PVP） blended Na＋ ion conducting solid polymeric membranes：（1-x） [75PEO：25NaPO3] ＋ x PVP, where 0 〈 x 〈 12 wt%, are reported. The polymeric blending was done using a solvent- free hot-press method. Two orders of conductivity enhancement （σca. 1.07× 10^-5 S·cm^-1） have been achieved with 3 wt% of PVP （i.e. the composition： [97（75PEO：25NaPO3）＋ 3PVP]）, from that of the pure host：（75PEO：25NaPO3）. The conductivity enhancement in PEO-PVP blended solid polymeric membranes have been explained by the ionic conductivity, ionic mobility and mobile ion concentration measurements. Materials characterization and polymer-salt complexation were done with the help of X-ray diffraction （XRD）, scanning electron microscopy （SEM）, differential scanning calorimetry （DSC） and thermo gravimetric analysis （TGA） studies. The temperature dependent conductivity studies have also been done to compute the activation energy （Ea） values from lgσ-1/TArrhenius plots. A solid state polymeric battery was fabricated by using optimum conducting composition of solid polymer electrolyte （SPE OCC）, and some important cell parameters were also calculated from the discharge profile of the cell.

关键词： Polymer blending Activation energy Ionic conductivity SEM XRD DSC TGA.