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191.
Li-Hua Wang 《Thermochimica Acta》2006,443(1):132-135
Calorimetric titration and NMR experiments in aqueous phosphate buffer (pH 7.2) at 298.15 K have been done to determine the binding mode, complex stability constants and thermodynamics (ΔG°, ΔH°, and TΔS°) for 1:1 inclusion complexation of water-soluble calix[n]arenesulfonates (CnAS, n = 4 and 6) and thiacalix[4]arene tetrasulfonate (TCAS) with acethylcholine, carnitine, betaine and benzyltrimethylammonium ion. The results show the inclusion complexations are driven by enthalpy (ΔH° < 0), accompanied by negative entropic changes (ΔS° < 0). The binding affinities (C4AS > C6AS > TCAS) are discussed from the viewpoint of CH-π/π-π interactions, electrostatic interactions and size/shape-fit relationship between host and guest. 相似文献
192.
193.
高密度数字视盘(HD-DVD)是一种新型蓝光存储技术,可以满足数字高清视频节目的播放要求.介绍了用于HD-DVD驱动器中的刀口法调焦方案,基于菲涅耳公式和标量衍射理论,推导了刀口法调焦的HD-DVD驱动器中聚焦误差信号与离焦量之间关系的计算模型.应用该计算模型,分析了不同离焦量时探测器上光强分布情况.计算得到的聚焦误差信号与离焦量之间的关系曲线与实验测得的“S型”曲线相一致,证明了计算模型的正确性.进一步分析了正焦点时由于记录符调制而引起的聚焦误差的干扰信号,计算结果表明这种干扰的强度小于4.5%.分析表
关键词:
光存储
刀口法
聚焦误差
标量衍射 相似文献
194.
A series of the title composites was synthesized by addition of modified attapulgite to polyurethane. Their structure and properties were studied by Fourier transform infrared (FT-IR) spectrometer, scanning electron microscope (SEM), etc. The results showed that such modification improves the structure of the carrier, while the chemical stability was improved by about 10?°C. Based on results of microbial activity and proliferation experiments, we conclude that use of modified attapulgite can increase the biologically active groups on the carrier as well as improving its ability to fix microbes. Good results can be achieved by adding 2.5?wt.% modified attapulgite. 相似文献
195.
By globally analyzing nuclear Drell-Yan data including all incident energies,the nuclear effects of nuclear parton distribution functions(nPDFs)and initial-state parton energy loss are investigated.Based on the Landau-Pomeranchuk-Migdal(LPM)regime,the calculations are carried out by means of analytic parametrizations of quenching weights derived from the Baier-Dokshitzer-Mueller-Peigné-Schiff(BDMPS)formalism and using the new EPPS16 nPDFs.It is found that the results are in good agreement with the data and the role of the energy loss effect in the suppression of Drell-Yan ratios is prominent,especially for low-mass Drell-Yan measurements.Thenuclear effects of nPDFs become more obvious with increasing nuclear mass number A,the same as the energy loss effect.By a global fit,the transport coefficient extracted is q=0.26±0.04 GeV2/fm.In addition,to avoid diminishing the QCD NLO correction to the data form of Drell-Yan ratios,separate calculations of the Compton differentialcross section ratios RFe(W)/C(xF)at 120 GeV are performed,which provides a feasible way to better distinguish the gluon energy loss in Compton scattering.It is found that the role of the initial-state gluon energy loss in the suppression of Compton scattering ratios is not very important and disappears with the increase of xF. 相似文献
196.
A scheme is presented for generating entangled states of multiple
atoms in a cavity. In the scheme the atoms simultaneously interact
with a cavity mode, with the first atom driven by two classical
fields and the other atoms driven by a classical field. Our scheme
is valid even if the cavity decay rate is larger than the effective
coupling strength, which is important for experiment. The generation
of entangled states is conditional on the detection of a photon
decaying from the cavity and thus the fidelity of the entangled
state is insensitive to the detection inefficiency. Furthermore, the
scheme can be applied to the case with any number of atoms in
principle. 相似文献
197.
We present a physical scheme to teleport an unknown atomic entangled state via cavity decay. In the teleportation process, four-particle Greenberger-Horne-Zeilinger (GHZ) state is used as quantum channel, and two unknown entangled atoms and two of four atoms in the four-particle GHZ state are trapped in four leaky cavities,respectively. Based on the joint detection of the photons leak out from the four cavities, we can teleport an unknown entangled state to two other remote atoms with certain probability and high fidelity. 相似文献
198.
199.
High spin states in 107Ag are studied via the 100Mo(11B, 4n)107Ag reaction at an incident beam energy of 60 MeV. Prompt γ-γ coincidence and DCO ratios are measured by the detector arrays in CIAE. The level scheme has been updated and a new negative band belonging to 107Ag is identified. The new negative side band has been constructed and its configuration is tentatively assigned to πg9/2 νh11/2(g7/2/d5/2). 相似文献
200.
We investigate the nonsequential double ionization(NSDI) of linear triatomic molecules by the counter-rotating two-color circularly polarized(CRTC) laser fields with a classical ensemble method. The results of the simulation reveal that NSDI yield strongly connected with the relative phase. The trajectory tracking method shows that the return time of the electron is controlled by the relative phase. In addition, when we change the CRTC laser wavelengths, the relative phase of the maximum and minimum yield of NSDI also changes. This shows that the influence of the Coulomb potential in the triatomic molecules on the electron return process cannot be ignored. This work will effectively promote the electronic dynamics study of NSDI for the triatomic molecule. 相似文献