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Some aspects of the transition probability P(, ) between states , on unital *-algebras are discussed. It is shown that P increases under the action of any stochastic linear map T, i.e., P(T, T)P(, ). Some properties of P are derived in starting from a recently-proved characterization of the quantity in question.  相似文献   
23.
Ohne ZusammenfassungAlle Bezeichnungen und Literatur wie dort.  相似文献   
24.
The kinetics of the O3, OH and NO3 radical reactions with diazomethane were studied in smog chamber experiments employing long-path FTIR and PTR-ToF-MS detection. The rate coefficients were determined to be k CH2NN+O3?=?(3.2?±?0.4)?×?10?17 and k CH2NN+OH?=?(1.68?±?0.12)?×?10?10 cm3 molecule?1 s?1 at 295?±?3?K and 1013?±?30 hPa, whereas the CH2NN?+?NO3 reaction was too fast to be determined in the static smog chamber experiments. Formaldehyde was the sole product observed in all the reactions. The experimental results are supported by CCSD(T*)-F12a/aug-cc-pVTZ//M062X/aug-cc-pVTZ calculations showing the reactions to proceed exclusively via addition to the carbon atom. The atmospheric fate of diazomethane is discussed.  相似文献   
25.
In this work, hydrogen plasma etching of surface oxides was successfully accomplished on thin (~100 µm) planar n‐type Czochralski silicon wafers prior to intrinsic hydrogenated amorphous silicon [a‐Si:H(i)] deposition for heterojunction solar cells, using an industrial inductively coupled plasma‐enhanced chemical vapour deposition (ICPECVD) platform. The plasma etching process is intended as a dry alternative to the conventional wet‐chemical hydrofluoric acid (HF) dip for solar cell processing. After symmetrical deposition of an a‐Si:H(i) passivation layer, high effective carrier lifetimes of up to 3.7 ms are obtained, which are equivalent to effective surface recombination velocities of 1.3 cm s–1 and an implied open‐circuit voltage (Voc) of 741 mV. The passivation quality is excellent and comparable to other high quality a‐Si:H(i) passivation. High‐resolution transmission electron microscopy shows evidence of plasma‐silicon interactions and a sub‐nanometre interfacial layer. Using electron energy‐loss spectroscopy, this layer is further investigated and confirmed to be hydrogenated suboxide layers. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)  相似文献   
26.
A numerical simulation of attosecond harmonic pulse generation in a three-dimensional field-ionizing gas is presented. Calculated harmonic efficiencies quantitatively reproduce experimental findings. This allows a quantitative characterization of attosecond pulse generation revealing information currently not accessible by experiment. The rapid phase variation and spatiotemporal distortions of harmonics are smaller than anticipated, allowing focusing of 30-nm, 750-as pulses to intensities in excess of 10(13) W/cm(2). Feasibility of such pulses brings novel applications such as extreme ultraviolet nonlinear optics and attosecond pump probe spectroscopy within reach.  相似文献   
27.
The concept of using magnetic particles (seeds) as the implant for implant assisted-magnetic drug targeting (IA-MDT) was analyzed in vitro. Since this MDT system is being explored for use in capillaries, a highly porous (ε∼70%), highly tortuous, cylindrical, polyethylene polymer was prepared to mimic capillary tissue, and the seeds (magnetite nanoparticles) were already fixed within. The well-dispersed seeds were used to enhance the capture of 0.87 μm diameter magnetic drug carrier particles (MDCPs) (polydivinylbenzene embedded with 24.8 wt% magnetite) under flow conditions typically found in capillary networks. The effects of the fluid velocity (0.015–0.15 cm/s), magnetic field strength (0.0–250 mT), porous polymer magnetite content (0–7 wt%) and MDCP concentration (C=5 and 50 mg/L) on the capture efficiency (CE) of the MDCPs were studied. In all cases, when the magnetic field was applied, compared to when it was not, large increases in CE resulted; the CE increased even further when the magnetite seeds were present. The CE increased with increases in the magnetic field strength, porous polymer magnetite content and MDCP concentration. It decreased only with increases in the fluid velocity. Large magnetic field strengths were not necessary to induce MDCP capture by the seeds. A few hundred mT was sufficient. Overall, this first in vitro study of the magnetic seeding concept for IA-MDT was very encouraging, because it proved that magnetic particle seeds could serve as an effective implant for MDT systems, especially under conditions found in capillaries.  相似文献   
28.
We prove existence of large families of solutions of Einstein-complex scalar field equations with a negative cosmological constant, with a stationary or static metric and a time-periodic complex scalar field.  相似文献   
29.
We study the performance of multifractal detrended fluctuation analysis (MF-DFA) applied to long-term correlated and multifractal data records in the presence of additive white noise, short-term memory and periodicities. Such additions and disturbances that can be typically found in the observational records of various complex systems ranging from climate dynamics to physiology, network traffic, and finance. In monofractal records, we find that (i) additive white noise hardly results in spurious multifractality, but causes underestimated generalized Hurst exponents h(q) for all q values; (ii) short-range correlations lead to pronounced crossovers in the generalized fluctuation functions Fq(s) at positions that decrease with increasing moment q, thus causing significantly overestimated h(q) for small q and spurious multifractality; (iii) periodicities like seasonal trends (with standard deviations comparable with the one of the studied process) result in spurious “reversed” multifractality where h(q) increases with increasing q (except for very short time windows). We also show that in multifractal cascades moderate additions of noise, short-range memory, or periodic trends cause flawed results for h(q) with q<2, while h(q) with q>2 remains nearly unchanged.  相似文献   
30.

Background  

Interruption of mature axons activates a cascade of events in neuronal cell bodies which leads to various outcomes from functional regeneration in the PNS to the failure of any significant regeneration in the CNS. One factor which seems to play an important role in the molecular programs after axotomy is the stearoyl Coenzyme A-desaturase-1 (SCD-1). This enzyme is needed for the conversion of stearate into oleate. Beside its role in membrane synthesis, oleate could act as a neurotrophic factor, involved in signal transduction pathways via activation of protein kinases C.  相似文献   
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