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排序方式: 共有190条查询结果,搜索用时 62 毫秒
181.
We describe a simple method to measure the top quark mass in the
channel that may be useful in Run II of D? detector. The method is validated by applying it to the Run Ib eμ data. 相似文献
182.
JM Chatterjee M Saha Sarkar S Bhattacharya P Banerjee S Sarkar RP Singh S Murulithar RK Bhowmik 《Pramana》2001,57(1):165-169
High-spin states of 95,97Mo (Z=42, N=53,55) nuclei have been investigated through 82Se(18O, xn) reaction at Eb=60 MeV. The level scheme in 95Mo has been observed upto ≏ 10 MeV in the present experiment. The level structure shows mainly single particle character.
In 97Mo, the ground state level sequence has been extended to ≏ 4.5 MeV while the previous information had been up to 2.4 MeV.
A negative parity band built on 1437 keV (11/2−) excited state has been extended to 5.5 MeV. The structure seems to show a coexistence of single particle and collective
modes of excitation. Properties of both the nuclei have been compared with shell model calculations using OXBASH. 相似文献
183.
Background
Clinical spinal cord injury in domestic dogs provides a model population in which to test the efficacy of putative therapeutic interventions for human spinal cord injury. To achieve this potential a robust method of functional analysis is required so that statistical comparison of numerical data derived from treated and control animals can be achieved. 相似文献184.
Avelino Martín Miguel Mena Adrin Prez‐Redondo Carlos Ylamos 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):m157-m159
The reaction of the imide–nitride complex [{Ti(η5‐C5Me5)(μ‐NH)}3(μ3‐N)] with potassium iodide in pyridine at room temperature affords the adduct di‐μ‐iodido‐1:1′κ4I‐bis{tri‐μ3‐imido‐1:2:3κ3N;1:2:4κ3N;1:3:4κ3N‐μ3‐nitrido‐2:3:4κ3N‐tris[2,3,4(η5)‐pentamethylcyclopentadienyl](pyridine‐1κN)‐tetrahedro‐potassiumtrititanium(IV)}, [K2Ti6(C10H15)6I2N2(NH)6(C5H5N)2] or [(C5H5N)(μ‐I)K{(μ3‐NH)3Ti3(η5‐C5Me5)3(μ3‐N)}]2. The crystal structure contains two [KTi3N4] cube‐type units held together by two bridging I atoms. There is a centre of inversion located in the middle of this unprecedented discrete K2I2 unit. The geometry around K is best described as distorted trigonal prismatic, with three imide groups, two bridging I atoms and one pyridine ligand. 相似文献
185.
We compute the Hochschild cohomology groups HH?(A) in case A is a triangular string algebra, and show that its ring structure is trivial. 相似文献
186.
If there is a light Abelian gauge boson gamma' in the hidden sector its kinetic mixing with the photon can produce a hidden cosmic microwave background (HCMB). For meV masses, resonant oscillations gamma<-->gamma' happen after big bang nucleosynthesis (BBN) but before CMB decoupling, increasing the effective number of neutrinos Nnu(eff) and the baryon to photon ratio, and distorting the CMB blackbody spectrum. The agreement between BBN and CMB data provides new constraints. However, including Lyman-alpha data, Nnu(eff) > 3 is preferred. It is tempting to attribute this effect to the HCMB. The interesting parameter range will be tested in upcoming laboratory experiments. 相似文献
187.
Fabrício RS Pereira Andréa Alessio Maurício S Sercheli Tatiane Pedro Elizabeth Bilevicius Jane M Rondina Helka FB Ozelo Gabriela Castellano Roberto JM Covolan Benito P Damasceno Fernando Cendes 《BMC neuroscience》2010,11(1):1-13
Background
Recent studies have shown that the human right-hemispheric auditory cortex is particularly sensitive to reduction in sound quality, with an increase in distortion resulting in an amplification of the auditory N1m response measured in the magnetoencephalography (MEG). Here, we examined whether this sensitivity is specific to the processing of acoustic properties of speech or whether it can be observed also in the processing of sounds with a simple spectral structure. We degraded speech stimuli (vowel /a/), complex non-speech stimuli (a composite of five sinusoidals), and sinusoidal tones by decreasing the amplitude resolution of the signal waveform. The amplitude resolution was impoverished by reducing the number of bits to represent the signal samples. Auditory evoked magnetic fields (AEFs) were measured in the left and right hemisphere of sixteen healthy subjects.Results
We found that the AEF amplitudes increased significantly with stimulus distortion for all stimulus types, which indicates that the right-hemispheric N1m sensitivity is not related exclusively to degradation of acoustic properties of speech. In addition, the P1m and P2m responses were amplified with increasing distortion similarly in both hemispheres. The AEF latencies were not systematically affected by the distortion.Conclusions
We propose that the increased activity of AEFs reflects cortical processing of acoustic properties common to both speech and non-speech stimuli. More specifically, the enhancement is most likely caused by spectral changes brought about by the decrease of amplitude resolution, in particular the introduction of periodic, signal-dependent distortion to the original sound. Converging evidence suggests that the observed AEF amplification could reflect cortical sensitivity to periodic sounds. 相似文献188.
189.
190.
3D-printing has revolutionized various industries and scientific research by its substantial benefits such as fast prototyping, high accuracy, durability, and customized shapes. Fused deposition modeling has been used in the fabrication of 3D-printed nanocarbon electrodes. Utilization of these 3D-printed nanocarbon electrodes in the identification of organophosphates (OPs) such as parathion, methyl parathion, paraoxon, and fenitrothion, has not been reported. These compounds are highly toxic and used as chemical warfare agents and pesticides. Herein, we show that 3D-printing can be utilized for low-cost and diagnosis of priority nerve agents. 相似文献