<正>Objective:To screen the antimicrobial potential of three ethnomedicinal plants Chassalia curviflora Thw.(C.curviflora),Cyclea peltata Hook.F.& Thomson(C.peltata) and Euphorbia hirta ...L(E.hirta) used in folk medicines in Aarukani hills Kani tribe,Tamil Nadu,India against human bacterial pathogens.Methods:Antibacterial efficacy was performed by disc diffusion method against the pathogens viz.,Escherichia coli(E.coli)(ATCC 35218),Staphylococcus aureus (S.aureus)(ATCC 6538),Salmonella typhi(S.typhi)(MTCC 733),Proteus vulgaris(P.vulgaris), Proteus mirabilis(P.mirabilis) and Streptococcus pyogenes(S.pyogenes) and incubated for 24 h at 37°C.Results:The maximum degree of antibacterial activity was observed in C.peltata followed by C.curviflora.While E.hirta showed comparatively low degree of antibacterial activity.The methanolic extract of C.peltata showed the antibacterial activity against three pathogens viz.,S.pyogenes,P.vulgaris and E.coli with the inhibition zones 12 mm,10 mm and 9 mm,respectively,hexane extracts of C.peltata also showed the antibacterial activity against two selected pathogens viz.,P.vulgaris and P.mirabilis with 15 mm and 12 mm of inhibition zones.All the three different concentrations(025,0.50 & 0.75 mg/mL) of methanolic extract of C. peltata show the inhibitory effect on the three susceptible bacteria S.pyogenes,P.vulgaris and E. coli with the maximum inhibition in the highest concentration(0.75 mg/mL).The methanolic and hexane extracts of C.curviflora exhibited the antibacterial activity against only one bacterium each i.e.P.vulgaris and S.typhi with the maximum zone of inhibition 13 and 11 mm respectively. The methanolic and hexane extracts of E.hirta exhibited the antibacterial activity against only one bacterium Le.S.pyogenes with the maximum zone of inhibition 13 and 11 mm respectively. Conclusions:The present investigation revealed that the C.curviflora,C.peltata and E.hirta are potentially good source of antibacterial agents and demonstrates the importance of such plants in traditional medicines.
The main injector particle production (MIPP) experiment at Fermilab uses particle beams of charged pions, kaons, proton and antiproton with beam momenta of 5–90 GeV/c to measure particle production ...cross-sections of various nuclei including liquid hydrogen, MINOS target and thin targets of beryllium, carbon, bismuth and uranium. The physics motivation to perform such cross-section measurements is described here. Recent results on the analysis of NuMI target and forward neutron cross-sections are presented here. Preliminary cross-section measurements for 58 GeV/c proton on liquid hydrogen target are also presented. A new method is described to correct for low multiplicity inefficiencies in the trigger using KNO scaling.
In this study, a high-power, non-enzymatic glucose biofuel cell (GBFC) based on a nano/micro hybrid-structured Au anode is proposed. A uniformly distributed micro-hemispheric array of polycarbonate ...is fabricated for this novel electrode by hot embossing using a Ni mold. The nano/micro hybrid-structured Au anode is then fabricated by depositing an Au nanoparticle monolayer on the micro-hemispheric array using 1,6-hexanedithiol as a two-sided anchor. The cathode is composed of a graphene film-coated glassy carbon electrode. Nafion, a proton exchange membrane, is used to separate the anode and cathode and complete the battery assembly. Experimental results demonstrate that the proposed non-enzymatic GBFC has a high-power density of 10.7 mWcm−2, a high current density of 29.5 mAcm−2, an open-circuit voltage of 8.2 V, and a shorted-circuit current of 34 mA at room temperature. The energy conversion efficiency of the electrode is calculated to be 52.47%. In addition, the proposed GBFC possesses advantages such as ease of production on a large scale, low manufacturing cost, high repeatability, and long-term preservation. Therefore, it is highly feasible for commercialization and use in practical applications.
•We develope a high-power non-enzymatic glucose biofuel cell.•The novel anode consists of a micro/nano hybrid structure of gold.•The monolayer of Au nanoparticles significantly enhances the glucose oxidation.•The current density of 29.5 mA/cm2 occurs at the power density of 10.7 mW/cm2.•The energy conversion efficiency was calculated to be 52.47%.
This volume captures the contents of the talks given at the Workshop on Applications of High Intensity Proton Accelerators held at Fermilab Oct 19–21, 2009. This workshop brought together experts ...from a variety of disciplines to explore new and profound ways proton accelerators can be used in the future. The workshop explored uses of such a proton source for producing intense muon, kaon and neutrino beams as well as using the intense protons for new forms of nuclear reactors that go by the name Accelerator Driven Sub-critical systems that promise to increase our available nuclear fuel supply by orders of magnitude while at the same time solving the nuclear waste problem. Intense proton beams can also be used to produce short-lived nuclear isotopes that are important in the medical industry.
We describe the physics capabilities and status of the MIPP experiment which is scheduled to enter its physics data taking period during December 2004–July 2005. We show some of the results obtained ...from the engineering run that concluded in August 2004 and point out the unique features of MIPP that make it an ideal apparatus to study non-perturbative QCD properties.
We describe the state of analysis of the MIPP experiment, its plans to upgrade the experiment and the impact such an upgraded experiment will have on hypernuclear physics.
This paper proposes a new thin curved sensor/strip to measure the relative slip between pad and specimen under fretting condition. Since the relative contact displacement is an important parameter to ...categorize the fretting process, the measurement of contact displacement between pad and specimen is necessary. Because of high yield strength and the ability to return to its initial position even with notable deflection, the spring steel have chosen to fabricate the thin curved strip. Before the fabrication, the detailed Finite Element Analysis (FEA) of the thin curved sensor was carried out. The strip consists of different shapes (rectangular, circular and elliptical) of slots and the number of slots in each strip is varied from 2 to 6. The Strain Energy Approach (SEA) has been used to calculate the displacement for the curved strip and it was compared, verified and validated with its FEA and Experimental results. From FEA study of thin curved strip with slots, four configurations were chosen to measure micro level displacement between pad and specimen under fretting experiments. The study reveals that the increasing number and size of holes presented in the curved strip indicate that the increased in displacement and von-Mises stress values which offers the higher flexibility to the strip. The reduction in area and minimum thickness of the curved strip could be the reason for the decrease in the stiffness of the curved strip. This study explores the use of new simple and novel instrument/sensor to capture the micro level relative displacement between the pad and specimen under fretting condition.
Ternary nanocomposite composed of nickel oxide (NiO), multi-walled carbon nanotubes (CNTs), and reduced graphene oxide (RGO) was synthesized based on concept of nanoarchitectonics. During the ...solvothermal process, graphite oxide was reduced to RGO with concurrent uniform deposition of NiO nanoparticles on the surface of the RGO nanosheets and CNTs. Scanning and transmission electron microscopy observations revealed the uniform distribution of spherical NiO nanocrystals (average size 35 nm) on the CNTs and RGO. The electrochemical performances of NiO and the RGO/CNT/NiO ternary nanocomposite were evaluated by using cyclic voltammetry and chronopotentiometry techniques. A maximum specific capacitance of 367 F g
−1
was achieved for the ternary nanocomposite at a current density of 1 A g
−1
in 6 M KOH electrolyte, which is about 2.2 times greater than that of pristine NiO demonstrating a strong synergistic effect in this RGO/CNT/NiO ternary nanocomposite. Additionally, the ternary nanocomposite electrode showed excellent cycling stability retaining 94 % of the initial capacity after 1,000 cycles.
Ternary semiconductor Pb5Sb8S17 has been shown to be a candidate solar absorber. This work presents a new solar absorber of the same group – Pb5Sb8Se17. Pb5Sb8S17 precursor nanocrystals (NCs) are ...first synthesized using solution processing. A subsequent S to Se ion exchange transforms the Pb5Sb8S17 precursor into the monoclinic Pb5Sb8Se17-δ phase. The substitution of S by Se reduces the band gap Eg from 1.75 (Pb5Sb8S17) to 1.41 eV (Pb5Sb8Se17-δ), increasing the optical absorption band from 300 to 750 (Pb5Sb8S17) to 300–900 nm (Pb5Sb8Se17-δ). The Eg of 1.4 eV equals to the ideal Eg for the Shockley-Queisser-limit. Liquid-junction quantum dot-sensitized solar cells (QDSSCs) are fabricated from the Pb5Sb8Se17-δ NCs with three types of counter electrode (CE): Pt, Au and NiSe. The cell using NiSe CE yields the best PCE of 2.73% (1 sun). Under reduced sun intensities, the PCE increases to 5.47% (0.1 sun) and further to 5.91% (0.05 sun). The external quantum efficiency (EQE) spectrum yields an EQE-integrated photocurrent Jph of 26.8 mA/cm2. The PCE of Pb5Sb8Se17 is 50% higher than that of the host Pb5Sb8S17 (3.95%). The optimal Eg, a high Jph and a high PCE suggest that Pb5Sb8Se17-δ has potential to be an efficient solar absorber.
•First successful growth of the new solar absorber material Pb5Sb8Se17.•First demonstration of Pb5Sb8Se17 quantum dot-sensitized solar cells.•Pb5Sb8Se17 has an optimal Eg of 1.4 eV for the Shockley-Queisser-limit.•Pb5Sb8Se17 QDSSCs yield a high photocurrent of 26.8 mA/cm2.•Best PCE equals 5.91% (0.05 sun).
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