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81.
Kristiana T. Santoso Chen‐Yi Cheung Kiel Hards Gregory M. Cook Bridget L. Stocker Mattie S. M. Timmer 《化学:亚洲杂志》2019,14(8):1278-1285
A series of 2‐ and 7‐substituted phthalazinones was synthesised and their potential as anti‐tubercular drugs assessed via Mycobacterium tuberculosis (mc26230) growth inhibition assays. All phthalazinones tested showed growth inhibitory activity (MIC <100 μm ), and those compounds containing lipophilic and electron‐withdrawing groups generally exhibited better anti‐tubercular activity. Several lead compounds were identified, including 7‐((2‐amino‐6‐(4‐fluorophenyl)pyrimidin‐4‐yl)amino)‐2‐heptylphthalazin‐1(2H)‐one (MIC=1.6 μm ), 4‐tertbutylphthalazin‐2(1H)‐one (MIC=3 μm ), and 7‐nitro‐phthalazin‐1(2H)‐one (MIC=3 μm ). Mode of action studies indicated that selected pyrimidinyl‐phthalazinones may interfere with NADH oxidation, however, the mode of action of the lead compound is independent of this enzyme. MIC=minimum inhibitory concentration. 相似文献
82.
We present a method to quantify spatial fluctuations of the substitution rate on different length scales throughout genomes of eukaryotes. The fluctuations on large length scales are found to be predominantly a consequence of a coarse-graining effect of fluctuations on shorter length scales. This is verified for both the mouse and the human genome. We also found that the relative standard deviation of fluctuations in substitution rate is about a factor three smaller in mouse than in human. The method allows furthermore to determine time-resolved substitution rate maps of the genomes, where the corresponding autocorrelation functions quantify the velocity of spatial chromosomal reorganization. 相似文献
83.
We present methods for detecting phase synchronization of two unidirectionally coupled, self-sustained noisy oscillators from a signal of the driven oscillator alone. One method detects soft phase locking; another hard phase locking. Both are applied to the problem of detecting phase synchronization in von Kármán vortex flow meters. 相似文献
84.
The development of a gas sampler for a miniaturized ambient ammonia detector is described. A micromachined channel system is realized in glass and silicon using powder blasting and anodic bonding. The analyte gas is directly mixed with purified water, dissolving the ammonia that will dissociate into ammonium ions. Carrier gas bubbles are subsequently removed from the liquid stream through a venting hole sealed with a microporous water repellent PTFE membrane. A flow restrictor is placed at the outlet of the sampler to create a small overpressure underneath the membrane, enabling the gas to leave through the membrane. Experiments with a gas flow of 1 ml min(-1), containing ammonia concentrations ranging from 9.4 ppm to 0.6 ppm in a nitrogen carrier flow have been carried out, at a water flow of 20 microl min(-1). The ammonium concentration in the sample solution is measured with an electrolyte conductivity detector. The measured values correspond with the concentration calculated from the initial ammonia concentration in the analyte gas, the fifty times concentration enhancement due to the gas-liquid volume difference and the theoretical dissociation equilibrium as a function of the resulting pH. 相似文献
85.
86.
Timmer MS Verdoes M Sliedregt LA van der Marel GA van Boom JH Overkleeft HS 《The Journal of organic chemistry》2003,68(24):9406-9411
An efficient and high-yielding solid-phase synthesis of a small library of compounds containing a cis-fused pyranofuran structural motive is described. With use of the cheap and readily available D-(+)-mannitol, a highly functionalized sugar template was synthesized and immobilized on a solid support via an olefinic linker. Modification of this two-point molecular scaffold and subsequent ring-closing metathesis/cleavage gave access to a series of functionalized conformationally constrained fused oxacycles. 相似文献
87.
B. C. Metsch G. A. Timmer R. van der Heyden P. W. M. Glaudemans 《Zeitschrift für Physik A Hadrons and Nuclei》1982,306(2):105-111
The influence of the various components of the Preedom-Wildenthal interaction — viz. central, tensor, spin-orbit (LS) and antisymmetric spin-orbit (ALS) — on properties ofA=20–22 nuclei is investigated. The effects of the LS and the ALS component on spectroscopic observables are found to be very similar. It is shown that it is possible to remove the ALS component, which component is absent in the free-nucleon-nucleon interaction, in favour of an enhanced LS component, without spoiling the agreement with experiment. Furthermore it was found that a similarity of the effects of the various components on the properties of states inA=21,T=1/2 leads to a classification of these levels into groups that can be interpreted as collective bands. 相似文献
88.
Particle-gamma angular correlations have been measured with the 29Si(α,pγ)32P reaction at bombarding energies Eα = 10.65, 10.69 and 11.00 MeV. Together with DSA lifetime measurements these experiments lead to seven unambiguous spin assignments to levels below 3.5 MeV excitation energy in 32P. In addition, the measured mixing ratios and branching ratios yield many dipole and quadrupole transition strengths. The previously known 3.44 MeV level is a doublet with components at 3 443.0±0.6 and 3 444.0±0.9 keV. 相似文献
89.
Comparison of the nuclear spectra in the mass region A = 10–40 shows a systematic difference between states of positive and negative parity. This systematic difference can be explained quantitatively with methods derived from statistical spectroscopy. The influence of spurious states is corrected for. 相似文献
90.