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1.
We introduce a new integrable model to investigate the dynamics of two component quasi-particle condensates with spatiotemporal interaction strengths. We derive the associated Lax pair of the coupled Gross-Pitaevskii (GP) equation and construct matter wave solitons, We show that the spatiotemporal binary interaction strengths not only facilitate the stabilization of the condensates, but also enables one to fabricate condensates with desirable densities, geometries, and properties, leading to the so-called "designer quasi-particle condensates". 相似文献
2.
LIU Zhenqing 《声学学报:英文版》1995,(4)
I.IntroductionBymeansofu1trasonicwavesthedynamicspecificpropertiesofmolecu1esinmediacouldbeapprehended.Fromthe195ostol96osacousticiansstudiedmo1ecu1aracousticandthermodynamicspecificpropertiesof1iquidsandmixtureswithgreate.th.siasm['-'],andkeptonbringto1ighttheirreportsofrc1evantstudiesinthe1astten-oddyearsl'-'l.overrecentyearstheauthorhasbeenengagedinthemeasurementandstudyofsoundve-locityofsevera1chemica1so1utionsinassociationwithu1trasonicmeasurementstudyofthecon-centrationofsolutionsproduce… 相似文献
3.
The electron paramagnetic resonance spectra of γ-irradiated powders of α-(methylamino)isobutyric acid – CH3NHC(CH3)2COOH, α -aminoisobutyric acid methyl ester hydrochloride – NH2(CH3)2CCOOCH3 HCl, and diethylmalonic acid – (CH3CH2)2C(COOH)2 have been investigated at room temperature. It has been found that γ -irradiation produces the (CH3)2C˙COOH radical in the first, the (CH3)2C˙COOCH3 radical in the second and the (CH3CH2)2C˙COOH radical in the third compound. The spectra were computer-simulated. The g values and the hyperfine coupling constants of the unpaired electron with the environmental methyl, methylene protons and OH proton were determined. The results were found to be in good agreement with the existing literature data and theoretical predictions. 相似文献
4.
The electron paramagnetic resonance of γ-irradiated single crystals of three-furancarboxylic acid has been studied for different orientations of the crystals in a magnetic field. The radicals produced by γ-irradiation have been investigated between 123 and 350 K. The spectra were found to be temperature dependent, and radiation damage centers were attributed to the radical. The principal values of the g-tensor were determined. The results were found to be in good agreement with the existing literature data and theoretical predictions. 相似文献
5.
I.InstrumentUltrasonichydroch1oricacidconcentrationmeter(Fig.l)measureson-linetheconccntra-honofhydroch1oricacidsolutioninwhichtheultrasonicve1ocitychangeswiththevariationoftheconcentrationandtemperatureoftheso1ution[1].Theconcentrationofhydrochloricacidso1utiotiwithdifferentconcentrationcanbegiven[']asD=ffc,T,P)(l)wherecistheu1trasonicvc1ocityinhydroch1oricacidsolution,Tisthctemperatilreofhydrochloricacidso1utionandPisthepressureofhydroch1oricacidsolution.Whenthcprcs-surePisaconstanLtheco… 相似文献
6.
Quantum calculations and experiments with molecular beams have been
carried out for the Formic Acid dimeric structures colliding with a
beam of slow (<20 ev) electrons.=" the=" corresponding=" computed=" s-matrix=" poles,=" seen=" as=" signatures=" for=" the=" formation=" of=" transient=" negative=" ions,=" allow=" us=" to=" assign=" the=" resonances=" to=" specific=" doorway=" states=" which=" are=" suggested=" to=" be=" responsible=" for=" the=" fragmentation=" patterns=" observed=" in=" the=" present=" experiments=" and=" in=" earlier=" measurements=" carried=" out=" both=" in=" molecular=" beams=" and=" with=" films=" of=" formic=" acid.=" we=" further=" show=" the=" computed=" behaviour=" of=" partial=" cross-sections=" and=" partial=" eigenphase=" sums=" for=" the=" dominant=" symmetry=" components.=">20 ev)> 相似文献
7.
MeiDong JianjuoWang YuhanSun 《北京同步辐射装置》2001,(1):138-144
The zincosilicate analog of zeolite mordenite was hydrothermally synthesized in the presence of citric acid and characterized with several spectroscopic techniques.The zeolite thus prepared had a higher crystallinity and Zn concentration in the framework compared with the one obtained in the absence of citric acid.XRD and FTIR provided evidence for the incorporation of Zn in the framework.Results of XAFS indicated a tetrahedral structure of Zn in the lattice framework with a Zn-O distancd of 0.1938nm.It is speculated that the citric acid might decrease the concentration of Zn^2 in the synthesis mixture,there by preventing the unfavorable-formation of oxide or hydroxide species.2001 Elsevier Science B.V.All rights reserved. 相似文献
8.
Angsula Ghosh 《Molecular physics》2013,111(5):497-507
The influence of the hydrogen-bond formation on the NMR spin–spin coupling constants, including the Fermi contact, the diamagnetic spin–orbit, the paramagnetic spin–orbit and the spin dipole term, has been investigated for the ortho-aminobenzoic acid microhydrated with up to three water molecules. The one-bond and two-bond spin–spin coupling constants for several intra-molecular and across-the-hydrogen-bond atomic pairs are calculated employing high-level density functional theory in combination with the B3LYP functional with two different types of extended basis sets for each level of microhydration. The spin–spin coupling constants, in general, vary inversely with the hydrogen bond length. The Fermi contact term is found to be the dominant contributor to the total value of spin–spin coupling constant followed by the paramagnetic spin–orbit term. The variations of Fermi contact term and atomic charge distribution with size of microhydration follow quite similar trend. The effect of explicit solvation provided by microhydration has also been compared briefly with that of bulk implicit solvation obtained through polarised continuum model and mixed microhydration/continuum approach. 相似文献
9.
B.H. Lee E.C. Wood J. Wormhoudt J.H. Shorter S.C. Herndon M.S. Zahniser J.W. Munger 《Journal of Quantitative Spectroscopy & Radiative Transfer》2012,113(15):1905-1912
We determined the effective line strengths of the trans conformer of nitrous acid (HONO) near 1275 cm?1 (R-branch of ν3 mode, NOH bend) and of the cis conformer at 1660 cm?1 (R-branch of ν2 mode, NO stretch), both at a spectral resolution of 0.001 cm?1 by tunable infrared laser differential absorption spectroscopy (TILDAS) utilizing continuous-wave quantum cascade (cw-QC) lasers. Absorbance of one conformer was measured while simultaneously quantifying the mixing ratio of total HONO by catalytic conversion to nitric oxide (NO) followed by calibrated absorption spectroscopy. Line strengths obtained here are consistent with previously reported band strengths for the trans conformer but are lower by a factor of approximately 2.4 for the cis conformer. 相似文献
10.
Janice Duy Laurie B. Connell Wolfgang Eck Scott D. Collins Rosemary L. Smith 《Journal of nanoparticle research》2010,12(7):2363-2369
A simple, two-step method of producing stable and functional peptide nucleic acid (PNA)-conjugated gold nanoparticles using a surfactant stabilization step is presented. PNA are DNA analogs with superior chemical stability and target discrimination, but their use in metallic nanoparticle systems has been limited by the difficulty of producing stable colloids of nanoparticle–PNA conjugates. In this work, the nonionic surfactant Tween 20 (polyoxyethylene (20) sorbitan monolaurate) was used to sterically shield gold surfaces prior to the addition of thiolated PNA, producing conjugates which remain dispersed in solution and retain the ability to hybridize to complementary nucleic acid sequences. The conjugates were characterized using transmission electron microscopy, dynamic light scattering, and UV–visible absorbance spectroscopy. PNA attachment to gold nanoparticles was confirmed with an enzyme-linked immunoassay, while the ability of nanoparticle-bound PNA to hybridize to its complement was demonstrated using labeled DNA. 相似文献
11.
Fluorescence lifetimes are reported for a series of anilinonaphthalene sulfonate (ANS) probe molecules complexed with -cyclodextrin (-CD). The fluorescence decay kinetics are recovered by multifrequency phase and modulation measurements in concert with a global analysis scheme. In all cases studied, a continuous Lorentzian distribution of lifetimes is observed, resulting from the dynamical nature of the ANS--CD complex and free ANS. Trends are discussed and comparisons made between bound and free fluorophore and between different isomeric ANS structures. 相似文献
12.
13.
Measurements of the quasistatic and frequency dependent electric conductivity below 1 MHz were carried out on wet-spun, macroscopically oriented, calf thymus DNA bulk samples, thus effectively extending previous radio frequency data down to quasistatic time scales. The frequency dependence of the electrical conductivity in the frequency range of approximately 10(-3)-10(15) Hz agrees well with predictions of the hopping hole mechanism. Temperature dependence of the quasistatic electrical conductivity can be rather well described by the activated Arrhenius law with the activation energy of approximately 0.9 eV; however, based on the quality of the fits, the hopping ansatz cannot be ruled out. 相似文献
14.
The temperature dependence of the 14N nuclear quadrupole resonance frequency in hexamethylphosphorus traimide, P[N(CH3)2]3, and hexamethylphosphoric triamide, O=P[N(CH3)2]3, has been studied between 77 K and the melting points. Values for the torsional oscillation frequencies v t and the empirical parameter b, a function of v t and the associated moment of inertia I, and of the volume-dependence parameter α, are reported. The values are consistent with previously reported values for thiourea, S=C(NH2)2. 相似文献
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16.
Miao Shui Weidong Zheng Jie Shu Qingchun Wang Shan Gao Dan Xu Liangliang Chen Lin Feng Yuanlong Ren 《Current Applied Physics》2013,13(3):517-521
Lithium-ion battery cathode material Li1+xV3O8 is synthesized by a citric acid/tartaric acid assisted sol–gel method and sintered at 350 °C, 450 °C and 550 °C for 3 h for the formation of Li1+xV3O8 phase. The synthesized samples were fully characterized by FTIR, TG/DTA, XRD, SEM, EIS and charge–discharge tests. Li1+xV3O8 material synthesized by tartaric acid assisted route and sintered at 450 °C for 3 h shows best electro-chemical performance. It shows a high initial capacity of 249 mAh g?1 and still reserves a discharge capacity of 260 mAh g?1 after 50 cycles. Moreover, in the case of tartaric assisted products, no capacity decadence is observed in 50 cycles. XRD together with TG/DTA measurements reveal that compared with citric acid assisted products, the adoption of tartaric acid as chelating agent effectively lowers the crystallization temperature of amorphous Li1+xV3O8. Therefore, precursors obtained by tartaric acid route calcinated at 450 °C for 3 h exhibit lower crystallinity and smaller grain size, which contributes to the better electrochemical performance of the cathode electrodes. From EIS measurements, the bulk resistance is reduced, which favors the intercalation and de-intercalation of lithium ions while cycling. 相似文献
17.
Fe nanoparticle (NP)-assembled thin films with different thickness were prepared by femtosecond-pulsed laser deposition using different deposition times. The proper selection of the deposition time allows to control, to a certain degree, the morphology and topology of the deposited Fe nanoparticles (NPs) assembly, fostering non-uniform dense assemblies of NPs, with the consequent reduction of the influence of the exchange interactions on the macroscopic magnetic properties with decreasing thickness. The magnetic behavior of the Fe NP-assembled films with decreasing thickness is characterized by higher coercive field (H c) values (a factor ≈4.5) and a good compromise between the hysteresis loops squareness and moderate exchange interactions, strongly correlated with the NPs topology. 相似文献
18.
Kunihiko OBATA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2013,89(4):139-156
Signal transmission through synapses connecting two neurons is mediated by release of neurotransmitter from the presynaptic axon terminals and activation of its receptor at the postsynaptic neurons. γ-Aminobutyric acid (GABA), non-protein amino acid formed by decarboxylation of glutamic acid, is a principal neurotransmitter at inhibitory synapses of vertebrate and invertebrate nervous system. On one hand glutamic acid serves as a principal excitatory neurotransmitter. This article reviews GABA researches on; (1) synaptic inhibition by membrane hyperpolarization, (2) exclusive localization in inhibitory neurons, (3) release from inhibitory neurons, (4) excitatory action at developmental stage, (5) phenotype of GABA-deficient mouse produced by gene-targeting, (6) developmental adjustment of neural network and (7) neurological/psychiatric disorder. In the end, GABA functions in simple nervous system and plants, and non-amino acid neurotransmitters were supplemented. 相似文献
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20.
Gaussian analysis (LinkFit program) was used to deconvolute overlapping absorption bands due to neutral and anionic forms
of ascorbic acid (AA). It has been shown that the neutral form of AA predominates in aqueous solutions of AA containing dialkylsulfoxides
(DASO) because a hydrogen-bonded complex forms between DASO and AA molecules. 相似文献