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1.
A facile synthetic strategy towards conformationally stable chiral chromophores based on dimeric porphyrinoids has been established. A peculiar class of face-to-face intramolecularly interlocked corrole dimers were formed by the oxidative C−C coupling linked at the inner carbon sites upon simple treatment of copper(II) ions. Their intrinsic electronic structures were modulated by the peripheral corrole ring annulations, which lead to distinct optical properties and redox profiles. The stereogenic carbon centers implemented in the confused corrole skeleton provided a rationale for designing novel chiral materials.  相似文献   
2.
Tetraoctylammonium cation forms a room-temperature molten salt (RTMS) with 2,4,6-trinitrophenolate anion. The RTMS is immiscible with water (W) and forms a stable RTMS/W interface. It has been shown that the RTMS/W interface can be electrochemically polarized. A well-defined voltammetric wave due to the transfer of thiocyanate ion across the RTMS/W interface was observed within the potential window. This is the first example of a polarized RTMS/W interface.  相似文献   
3.
Taking into account pseudoscalar as well as scalar condensates, we reexamine the chiral restoration path on the chiral manifold. We shall see both condensates coherently produce a density wave at a certain density, which delays chiral restoration as density or temperature is increased.  相似文献   
4.
This paper focuses on masking speech with meaningless steady noise as a way of realizing a comfortable sound environment. As a basis for research, meaningless steady noise at minimum sound pressure levels for masking of male or female meaningful speech is considered, based on psychological experiments using a method of adjustment. From the results, band-limited pink noise can be selected as the most effective noise for masking of speech. In the case of speech with a lower sound pressure level, the sound pressure level of the meaningless steady noise needs to be a little higher.  相似文献   
5.
6.
We have recently reported on dodecamer peptides (HPPMDFHKAMTR, CHPQPLKSRNPL) which recognize 52-58th and 197-203rd amino acid sequences of glucose oxidase (GOx) by screening via a phage random peptide library. In this study, a side-chain protected peptide monomer (PPM) was synthesized using two peptides (HPPMDFHKAMTR, SHPQPLKSRNPL) and acryloyl chloride. The peptide-conjugated polymer (PCP) was copolymerized with PPMs and N,N-diethylacrylamide (DEAA). The affinity of PCPs to GOx was estimated using surface plasmon resonance detection. This study suggests that PCP is a valuable molecular recognition biomolecule.  相似文献   
7.
The oxygen storage capacity of CeO2, Ce0.9Pr0.1O2, Pt?Rh/CeO2 and Pt?Rh/Ce0.9Pr0.1O2 was investigated by conventional GC pulse method and transient pulse techniques. It is shown that incorporation of PrOy into CeO2 matrix strongly promotes oxygen storage capacity (OSC) measured using the transient pulse technique. The improvement of OSC at low temperature is observed in Pt?Rh loaded onto CeO2 and Ce?Pr catalysts.  相似文献   
8.
A series of gel polymer electrolytes containing PVdF as homo polymer, a mixture of 1:1 Ethylene Carbonate (EC) : Propylene Carbonate (PC) as plasticizer and lithium-bistrifluoromethane sulphone imide [imide — LiN (CF3SO2)2] has been developed. Amounts of polymer (PVdF), plasticizer and the imide lithium salt have been varied as a function of their weight ratio composition in this regard. Dimensionally stable films possessing appreciable room temperature conductivity values have been obtained with respect to certain weight ratio compositions. However, conductivity data have been recorded at different possible temperatures, i.e., from 20 °C to 65 °C. XRD and DSC studies were carried out to characterize the polymer films for better amorphicity and reduced glass transition temperature, respectively. The electrochemical interface stability of the PVdF based gel polymer electrolytes over a range of storage period (24 h – 10 days) have been investigated using A.C. impedance studies. Test cells containing Li/gel polymer electrolyte (GPE)/Li have been subjected to undergo 50 charge-discharge cycles in order to understand the electrochemical performance behaviour of the dimensionally stable films of superior conductivity. The observed capacity fade of less than 20% even after 50 cycles is in favour of the electrochemical stability of the gel polymer electrolyte containing 27.5% PVdF −67.5 % EC+PC −5% imide salt. Cyclic voltammetry studies establish the possibility of a reversible intercalation — deintercalation process involving Li+ ions through the gel polymer electrolyte.  相似文献   
9.
A new, wide-band, high-speed and high-sensitivity THz detector has been developed. The prototype detector consists of a parabolic cylindrical mirror, a long wire antenna and a Schottky barrier diode. Direct detection measurements have shown a stable sensitivity of 150 ± 50 V/W for 1–2 THz without any adjustments. The long wire antenna was fixed at the focus of parabolic cylindrical mirror then it has been realized less operation steps, easy coupling to the external THz signals and a dramatic enhancement in the practicality of this system. The optically polished mirror and frosted surface one showed comparable sensitivities, thus easy polishing and less cost mirror fabrication can be applied for this system. The radiation pattern showed a maximum radiation angle of approximately 23° with its dominant main lobe, which was attributed to the wire antenna character and confirmed good agreements with classical antenna theory.  相似文献   
10.
We propose a new detection method for a pseudo-random frequency modulation continuous wave (RM-CW) coherent lidar. The feature of this method is modulation of local beam with a time delayed pseudo-random sequence. Heterodyne detection and correlation detection between the received beam and the local beam are simultaneously carried out in an optical field. In the RM-CW coherent lidar using the optical field correlation detection method, the received equipment is greatly simplified. We carried out preliminary experiments and demonstrated that the new method is effective for detection of a CW coherent lidar.  相似文献   
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