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991.
Kyung-Hyun Choi Arshad Khan Khalid Rahman Yang-Hoi Doh Dong-Soo Kim Ki-Rin Kwan 《Journal of Electrostatics》2011,69(4):380-387
This paper presents the analysis of a triangular array of nozzles in a multi-nozzle electrohydrodynamic (EHD) inkjet printing head. A methodology has been proposed to minimize the “end effect” by changing the traditional linear array of nozzles to triangular array of nozzles in multi-nozzle EHD printing head. Interaction (cross-talk) between the electrically charged neighboring jets is investigated and analyzed both numerically and experimentally using three glass nozzles with independent voltage connections and independent ink supply to each nozzle. In order to scrutinize the performance of triangular array multi-nozzle EHD inkjet printing head, comparative study of triangular array multi-nozzle EHD inkjet printing head to the linear array multi-nozzle EHD inkjet printing head has been made on the basis of electric field simulations and experiments. Experimental results illustrate that in triangular array multi-nozzle EHD inkjet printing head, the over potential requirement is low and individual capillaries are operating with more independence as compared to linear array multi-nozzle EHD inkjet printing head. 相似文献
992.
We examine the behavior of the leading Regge trajectory of the open bosonic string in a uniform electromagnetic background and present a consistent set of Fierz–Pauli conditions for these symmetric tensors that generalizes the Argyres–Nappi spin-2 result. These equations indicate that String Theory does bypass the Velo–Zwanziger problem, i.e. the loss of causality experienced by a massive high-spin field minimally coupled to electromagnetism. Moreover, we provide some evidence that only the first Regge trajectory can be described in isolation and show that the open-string spectrum is free of ghosts in weak constant backgrounds. Finally, we comment on the roles of the critical dimension and of the gyromagnetic ratio. 相似文献
993.
Mohammed M. Rahman A. Jamal Sher Bahadar Khan M. Faisal 《Superlattices and Microstructures》2011,50(4):369-376
Hydrothermally prepared as-grown low-dimensional nano-particles (NPs) have been characterized using UV–vis spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, and electron dispersion spectroscopy (EDS). The uniformity of the nano-material was executed by the scanning electron microscopy, where the single phase of the nano-crystalline β-Fe2O3 was characterized using XRD techniques. β-Fe2O3 nanoparticles fabricated glassy carbon electrode (GCE) have improved chloroform-sensing performances in terms of electrical response (I–V technique) for detecting analyte in liquid phase. The analytical performances were investigated, which showed that the better sensitivity, stability, and reproducibility of the sensor improved significantly by using Fe2O3 NPs thin-film on GCE. The calibration plot was linear (R = 0.9785) over the large range of 12.0 μM to 12.0 mM. The sensitivity was calculated as 2.1792 μA cm−2 mM−1 with a detection limit of 4.4 ± 0.10 μM in short response time (10.0 s). 相似文献
994.
Abdul‐Rahman Allouche 《Journal of computational chemistry》2011,32(1):174-182
Gabedit is a freeware graphical user interface, offering preprocessing and postprocessing adapted (to date) to nine computational chemistry software packages. It includes tools for editing, displaying, analyzing, converting, and animating molecular systems. A conformational search tool is implemented using a molecular mechanics or a semiempirical potential. Input files can be generated for the computational chemistry software supported by Gabedit. Some molecular properties of interest are processed directly from the output of the computational chemistry programs; others are calculated by Gabedit before display. Molecular orbitals, electron density, electrostatic potential, nuclear magnetic resonance shielding density, and any other volumetric data properties can be displayed. It can display electronic circular dichroism, UV–visible, infrared, and Raman‐computed spectra after a convolution. Gabedit can generate a Povray file for geometry, surfaces, contours, and color‐coded planes. Output can be exported to a selection of popular image and vector graphics file formats; the program can also generate a series of pictures for animation. Quantum mechanical electrostatic potentials can be calculated using the partial charges on atoms, or by solving the Poisson equation using the multigrid method. The atoms in molecule charges can also be calculated. Gabedit is platform independent. The code is distributed under free open source X11 style license and is available at http://gabedit.sourceforge.net/ . © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010 相似文献
995.
Nguyen Van Do Pham Duc Khue Kim Tien Thanh Tran Hoai Nam Md. Shakilur Rahman Kyung-Sook Kim Manwoo Lee Guinyun Kim Hee-Seock Lee Moo-Hyun Cho In Soo Ko Won Namkung 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):813-820
We measured the isomeric yield ratios for the 44m,gSc isomeric pairs produced from different reaction channels 45Sc(??,n)44m,gSc and natTi(??,xnp)44m,gSc by using the activation method and ??-ray spectroscopic methods at 50-, 60-, and 70-MeV bremsstrahlung energies. The high-purity natural Sc and Ti foils in disc shape were irradiated with uncollimated bremsstrahlung beams generated from an electron linear accelerator at Pohang Accelerator Laboratory. The induced activities in the irradiated foils were measured by the high-resolution ??-ray spectrometric system which consists of a high-purity Germanium detector and a multichannel analyzer. In order to improve the accuracy of the experimental results the necessary corrections were made in the ??-ray activity measurements and data analysis. The measured isomeric yield ratios for the 45Sc(??,n)44m,gSc reaction are 0.20 ± 0.02, 0.21 ± 0.02, and 0.21 ± 0.02 and those for the natTi(??,xnp)44m,gSc reaction are 0.063 ± 0.012, 0.079 ± 0.014, and 0.124 ± 0.022 at 50-, 60-, and 70-MeV bremsstrahlung energies, respectively. The obtained results are compared with the corresponding values found in the literature. We observed that the isomeric yield ratios for the 45Sc(??,n)44m,gSc reaction increase rapidly with the increasing bremsstrahlung energies from the reaction threshold up to giant resonance region, and then those are almost constant in the energy range from about 30 to 2.5 GeV. The isomeric yield ratios for the natTi(??,xnp)44m,gSc reaction increase with increasing bremsstrahlung energies in a wide range of bremsstrahlung energies from 50 to 2.5 GeV. 相似文献
996.
Kim D Sun D Lu W Cheng Z Zhu Y Le D Rahman TS Bartels L 《Langmuir : the ACS journal of surfaces and colloids》2011,27(18):11650-11653
Molybdenum disulfide (molybdenite) monolayer islands and flakes have been grown on a copper surface at comparatively low temperature and mild conditions through sulfur loading of the substrate using thiophenol (benzenethiol) followed by the evaporation of Mo atoms and annealing. The MoS(2) islands show a regular Moire? pattern in scanning tunneling microscopy, attesting to their atomic ordering and high quality. They are all aligned with the substrate high-symmetry directions providing for rotational-domain-free monolayer growth. 相似文献
997.
Synthesis and antimicrobial activity of new C‐furyl glycosides bearing substituted 1,3,4‐oxadiazoles
Wael A. El‐Sayed Hebat‐Allah S. Abbas Ashraf M. Mohamed Adel A.‐H. Abdel‐Rahman 《Journal of heterocyclic chemistry》2011,48(5):1006-1013
New 2,5‐disubstituted 1,3,4‐oxadiazole derivatives bearing C‐furyl glycoside moieties and their sugar hydrazone as well as their per‐O‐acetyl derivatives were synthesized starting from ethyl 2‐[5‐(3,4‐dihydroxytetrahydrofuran‐2‐yl)‐2‐methylfuran‐3‐yl]‐2‐oxoacetate. Heterocyclization of the sugar hydrazones using acetic anhydride afforded the corresponding oxadiazoline acyclic C‐nucleosides. The antimicrobial activity evaluation showed that many of the synthesized compounds revealed moderate to high antimicrobial activity. J. Heterocyclic Chem., (2011) 相似文献
998.
Synthesis of the title compounds was achieved using the anils 2a , 2b , 2c , 2d , 2e and 5a , 5b , 5c derived from the 4‐aminopyrazole 1 as starting materials. These compounds were allowed to react with mercaptoacetic acid in boiling dry benzene to afford the corresponding thiazolidinones and spiro‐thiazolidinones 3a , 3b , 3c , 3d , 3e and 6a , 6b , 6c , respectively. Pictet—Spengler reaction of the 4‐aminopyrazole hydrochloride 7 with aromatic aldehydes and cyclic ketones resulted in the formation of new pyrazolo[4,3‐e]pyrrolo[1,2‐a]pyrazines 8a , 8b , 8c , 8d , 8e and 9a , 9b , respectively. Other derivatives of pyrazolo pyrrolopyrazines 10 and 11 were obtained via the reaction of the amino derivative 1 with 1,1′‐carbonyldiimidazol and CS2, respectively. J. Heterocyclic Chem., (2011). 相似文献
999.
Mohammad A. Rahman Shishir Ghosh Graeme Hogarth Ebbe Nordlander 《Journal of organometallic chemistry》2011,696(2):607-612
Addition of tri(2-furyl)phosphine, PFu3, to [Os3(CO)10(μ-H)2] at room temperature gives [HOs3(CO)10(PFu3)(μ-H)] (1), while in refluxing toluene the same reactants afford [Os3(CO)9{μ3-PFu2(C4H2O)}(μ-H)] (2) resulting from orthometallatation of a furyl ring. Reaction of PFu3 with [Os3(CO)10−n(NCMe)n] (n = 0, 1, 2) affords the substituted clusters [Os3(CO)12−n(PFu3)n] (n = 1-3) (3-5), the phosphine ligands occupying equatorial position in all cases. Heating [Os3(CO)11(PFu3)] (3) in refluxing octane gives [Os3(CO)9(μ3-PFu)(μ3-η2-C4H2O)] (6) which results from both carbon-hydrogen and carbon-phosphorus bond activation and contains both μ3-η2-furyne and furylphosphinidene ligands. All new clusters have been characterized by spectroscopic methods together with single crystal X-ray diffraction for 2, 3 and 6. 相似文献
1000.
In this contribution, chemical sensor for the detection of aqueous ammonia has been fabricated using UV-curable polyurethane acrylate (PU) and nanohybrids (NH-1, NH-3 and NH-5). PU has been prepared by reacting polycaprolactone triol (PCLT) and isophorone diisocyanate (IPDI) while the nanohybrids, NH-1, NH-3, and NH-5 have been synthesized by solution blending method using PU with 1, 3, and 5 wt% loading levels of C-20B. PU and their nanohybrids showed higher sensitivity investigated by I-V technique using aqueous ammonia as a target chemical. All the nanohybrids showed higher sensitivity as compared to neat PU. The sensitivity increased with increase in clay content and the nanohybrid containing 5 wt% of clay showed the highest sensitivity (8.5254 μA cm−2 mM−1) with the limit of detection (LOD) of 0.0175 ± 0.001 μM, being 7.8 times higher than pure PU. The calibration plot for all the sensors was linear over the large range of 0.05 μM to 0.05 M. The response time of the fabricated sensor was <10.0 s. Therefore, one can fabricate efficient aqueous ammonia sensor by utilization of nanohybrid as an efficient electron mediator. 相似文献