Primary discussion on speech intelligibility of Chinese and the speech transmission index

The relation between the speech intelligibility of Chinese and thespeech transmission index(STI)is discussed,which is based on some useful proper-ties of the modulation transfer function(MTF)and the result obtained by articula-tion tests under different signal-to-noise ratios.     

The influence of doping on ultimate performance of photodiodes for the 8–14 μm spectral range

The zero-bias resistance-area product (R_oA) of LN₂ temperature Cd_xHg_1−xTe 8–14 μm range photodiodes has been calculated. The influence of the types: the Auger and the radiative recombination in p- and n-type regions was taken into account.It was shown that the photodiode ultimate performance is determined by the Auger 7 recombination in p-type material. The ultimate value of (R_oA) is about 8 Ω cm² and it is much lower than calculated in recent works.     

The effects of pulsed laser injection seeding and triggering on the temporal behavior and magnitude of laser-induced incandescence from soot

The effect of sub-nanosecond fluence fluctuations and triggering on time-resolved laser-induced incandescence (LII) from soot has been studied using an injection-seeded pulsed Nd:YAG laser that produces a smooth laser temporal profile. Without injection seeding, this multi-mode laser generates pulses with large intensity fluctuations with sub-nanosecond rise times. The experimental results described here demonstrate that at fluences below 0.6 J/cm² LII signals are insensitive to fluence fluctuations on nanosecond time scales. At fluences above 0.6 J/cm² fluctuations in the laser profile cause the rising edge of the LII profile to move around in time relative to the center of the laser pulse causing a broader average profile that shifts to earlier times. Such fluctuations also lead to a decrease in the average LII temporal profile by up to 12% at a fluence of 3.5 J/cm². A timing jitter on the trigger of the data acquisition, such as that produced by triggering on the laser Q-switch synchronization pulse, has a negligible effect on the shape and temporal maximum of the LII signal. Additional jitter, however, considerably reduces the peak of the LII temporal profiles at fluences as low as 0.15 J/cm². Neither fast fluence fluctuations nor trigger jitter have a significant effect on gated LII signals, such as those used to infer soot volume fraction.     

The effects of laser and electric field on sprouting of rice seeds

There is a number of reports on the laser-treatment of rice in these years.But wedidn't see any report about treating rice seeds with laser plus DC electric field.This paper re-ports the initial result of the strengthened seed vitality,having been treated by laser plus elec-tric field.     

Lithium-rich layered nickel–manganese oxides as high-performance cathode materials: the effects of composition and PEG on performance

Lithium-rich layered nickel–manganese oxide (LRL-NMO) as a cathode material for rechargeable lithium-ion batteries was successfully prepared using an oxalic acid co-precipitation method, with polyethylene glycol (PEG1000) as an additive. The effects of the Ni/Mn ratio and of PEG on the phase purity, morphology, and electrochemical performance of LRL-NMO were investigated with X-ray diffraction, scanning electron microscope, electrochemical impedance spectroscopy, and charge/discharge testing. Li[Li_0.167Ni_0.25Mn_0.580]O₂ delivered the best electrochemical performance among the various Li[Li_1/3?2x/3Ni _x Mn_2/3?x/3]O₂ (0?<?x?<?0.5) materials. Furthermore, the sample to which an appropriate amount of PEG had been added showed much smaller and more uniform particle size, higher discharge capacity and energy density, better cycling stability, and lower resistance. The material prepared by adding 9 wt% PEG exhibited high discharge capacity and stability; after 100 cycles at 2 C, it still delivered a discharge capacity of 125.6 mAh g^?1, which was 50 % higher than that of a sample prepared without PEG.     

The effects of deposition temperature and ambient on the physical and electrical performance of DC-sputtered n-ZnO/p-Si heterojunction

The effects of deposition conditions on the physical and electrical performance of the n-ZnO/p-Si heterojunction were systematically investigated. ZnO films were deposited on the Si and glass substrates using direct current (DC) magnetron sputtering with various ambients and substrate temperatures. The results showed that increasing the O₂ content and substrate temperature during the deposition process could improve the crystallinity and stoichiometry of the ZnO film, resulting in a lower carrier concentration and higher resistivity. The electrical properties of the n-ZnO/p-Si heterojunctions were also affected by the deposition parameters. For the junctions fabricated in the pure Ar ambient, the sample deposited at room temperature (RT) showed Ohmic behavior, while the one deposited at 300?°C exhibited poor rectifying behavior. On the other hand, the junctions fabricated in the O₂/Ar ambient possessed ideal rectifying behaviors. The different carrier transport mechanisms for the heterojunctions under forward and reverse bias were systematically studied using a high temperature current–voltage (I-V) measurement. The recombination-tunneling current showed temperature insensitive performance while the space-charge limited current (SCLC) changed with the measurement temperature.     

The effects of physical parameters on the gain and efficiency of Cherenkov type FEL

In this paper, the effects of physical parameters on the gain and efficiency of Cherenkov type FEL are studied through simulative compute. The results show that the permittivity ε and periodic length λ_(?) of wiggler magnetic filed are two important parameters which influence the properties of laser. The magnitude ε has effect on the properties of gain, and the choice of wigger λ_(?) can increase gain and efficiency of the laser. The calculation results show that the gain and efficiency of Cherenkov type FEL are considerably higher than those of Compton-Raman type FEL under some conditions with proper parameters.     

The effect of rubber dampers on engine’s NVH and thermal performance

Fins as extended surfaces are attached to the internal combustion engine surfaces for enhancing the heat transfer. However, these fins vibrate at various frequencies, which produce undesirable radiated noise. To mitigate this effect, automobile industry inserts rubber dampers between these fins. These rubber dampers reduce the fins’ amplitude of vibration and thus reduce the radiated noise from the fin surfaces. Investigations on the effect of rubber dampers on the engine’s NVH (Noise–Vibration–Harshness) and thermal performance using numerical (FEM and CFD) and experimental measurement have been presented in this paper. Experiments were conducted in the semi-anechoic chamber on an engine with and without rubber dampers to measure the radiated noise from the fins. It was found that rubber dampers assist in reducing engine high frequency noise signals at higher engine speeds. Modal and harmonic response analysis was carried out on various designs for NVH characteristics improvement. Prototypes of the final design was made and tested for the NVH performance. Computational fluid dynamics (CFD) simulations were performed on engine with and without rubber dampers to investigate the thermal performance. It was found that rubber dampers increase engine temperature by about 10%. Effect of rubbers dampers on the cost and environmental impact has also been discussed. This paper provides a systematic procedure to investigate the effect of rubber dampers and a method to eliminate these dampers from the engines with the same NVH and better thermal performances.     

The effects of Raman self-pumping and fiber loss on the transmission of fiber dark soliton

In this paper,the effects of Raman self-pumping and fiber loss on the transmis-sion of fundamental dark soliton and small-amplitude one are discussed with the perturbationmethod of energy-momentum and inverse scatter theory.It is demonstrated that the amplitudeof fundamental dark soliton will decay exponentially,while that of small amplitude dark soli-ton depends strongly on its propagation direction.     

The effects of electron–phonon interaction on anisotropic RKKY interaction in graphene nanoribbon

We study the Ruderman–Kittle–Kasuya–Yosida (RKKY) interaction in doped armchair graphene nanoribbon. The effects of both external magnetic field and electron-Holstein phonon on RKKY interaction have been addressed. RKKY interaction as a function of distance between localized moments has been analyzed. It has been shown that a magnetic field along the z-axis mediates an anisotropic interaction which corresponds to a XXZ model interaction between two magnetic moments. In order to calculate the exchange interaction along arbitrary direction between two magnetic moments, we should obtain both transverse and longitudinal static spin susceptibilities of armchair graphene nanoribbon in the presence of electron-phonon coupling and magnetic field. The spin susceptibility components are calculated using the spin dependent Green’s function approach for Holstein model Hamiltonian. The effects of spin polarization on the dependence of exchange interaction on distance between moments are investigated via calculating correlation function of spin density operators. Our results show the influences of magnetic field on the spatial behavior of in-plane and longitudinal RKKY interactions are different in the presence of magnetic field.     

The effects of high-energy ion irradiations on the I–V characteristics of silicon NPN transistors

The silicon NPN rf power transistors were irradiated with different linear energy transfer (LET) ions such as 50?MeV Li³⁺, 80?MeV C⁶⁺ and 150?MeV Ag¹²⁺ ions in the dose range of 1–100?Mrad. The SRIM simulation was used to understand the energy loss and range of these ions in the transistor structure. The different electrical parameters such as Gummel characteristics, excess base current (ΔI_B), DC current gain (h_FE), displacement damage factor (K) and output characteristics were systematically studied before and after irradiation. The ion irradiation results were compared with ⁶⁰Co-gamma irradiation result in the same dose range. A considerable increase in base current (I_B) and a decrease in h_FE and I_CSat were observed after irradiation. The degradation in the electrical parameters was comparably very high for Ag¹²⁺ ion-irradiated transistor when compared to other ion-irradiated transistors, whereas the degradation in the electrical parameters for Li³⁺ and C⁶⁺ ion-irradiated transistors was comparable with gamma-irradiated transistor. The isochronal annealing study was conducted on the 100?Mrad irradiated transistors up to 500°C to analyze the recovery in different electrical parameters. The h_FE and other electrical parameters of irradiated transistors were almost recovered after 500°C for 50?MeV Li³⁺, 80?MeV C⁶⁺ ion and ⁶⁰Co-gamma-irradiated transistors, whereas for 150?MeV Ag¹²⁺ ion-irradiated transistor, the recovery in electrical characteristics is not complete.     

The effects of deviations from Lorentz–Berthelot rules on the properties of a simple mixture

Generally, the parameters in the interaction potential between like molecules in a mixture can be determined in a relatively straightforward manner from the properties of the pure components. However, the determination of the parameters in the interaction potential between the unlike pairs in the mixtures is more difficult. As a result, these parameters are usually estimated from averages of the like parameters. The most common recipes are the Lorentz–Berthelot mixing rules, where the energy and molecular size parameters are presumed to be geometric and arithmetic averages, respectively. There have been some studies of the consequences of deviations from the energy rule but almost no studies of the consequences of deviations from the size rule. Here, we study the effects of deviations from both rules on the radial distribution functions of a simple mixture. We find from simulations that, for this mixture, the effect of deviations from the energy rule on the radial distribution function are rather small but that the effect of deviations from the size rule can be significant and are interesting.     

A comparative study on the effects of salt and filler on transport and structural properties of organic–inorganic hybrid electrolytes

Organic–inorganic hybrid electrolytes based on the reaction of tri-block copolymer poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol) bis(2-aminopropyl ether), poly(ethylene glycol diglycidyl ether, and (3-glycidyloxypropyl)trimethoxysilane doped with LiClO₄ and SiO₂ nanoparticles were synthesized by a sol–gel process. The structural and dynamic properties of the materials thus obtained were systematically investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, alternate current impedance, and ¹³C solid-state NMR measurements. A maximum ionic conductivity of 3.2?×?10^?5 S cm^?1 was obtained at 30 °C for the solid hybrid electrolyte with a [O]/[Li] ratio of 16 and 7 wt% of SiO₂ nanoparticles. A Vogel–Tamman–Fulcher-like temperature dependence of ionic conductivity was observed for the hybrid electrolytes, implying that the diffusion of charge carriers was assisted by the segmental motions of the polymer chains.     

Effect of spin–orbit coupling on spectral and transport properties of tubular electron gas in InAs nanowires

We constructed the Hamiltonian of spin–orbit splitting for carriers of a tubular electron gas in InAs nanowires. The spectral problem is solved using an exact numerical diagonalization. It is shown that the contribution of k-linear Dresselhaus-like spin–orbit (SO) coupling leads to renormalization of the so-called SO-gaps and appearance of anticrossings in subband spectrum. These features can be detected in ballistic transport.     

The effect of oil on the performance of heat pumps and refrigerators—II. Experimental results

The results of a prolonged investigation of the influence of the lubricating oil Shell Clavus 68 on the performance of an R12-based refrigeration-heat pump system are presented. The strategy is discussed for deciding if a given series of data collected at 10s intervals adequately represents the chosen experimental conditions and results are presented under both transient and steady state conditions. The effects of oil on evaporator capacity, coefficient of performance, heat transfer rates, evaporator outlet superheat stability, refrigerant mass flow rate, evaporator pressure drop and compressor discharge temperature are discussed, and the experimental results are compared with a theoretical analysis. Finally, it is shown that under certain (albeit unlikely) conditions, it is possible for both the evaporator and condensor to act as heat rejectors.     

A preparation method and effects of Al–Cr coating on NdFeB sintered magnets

A 50 μm Al–Cr coating on NdFeB sintered magnets was prepared through dipping in solution, shaking dry and heating at 300 °C. The morphology and composition of the Al–Cr coating were investigated with scanning electron microscope, energy dispersive spectrometer and X-ray diffraction. The corrosion resistance of NdFeB sintered magnets with and without the Al–Cr coating was analyzed by normal salt spray, polarization curves and electrochemical impedance spectroscopy. The magnetic properties were measured with a hysteresis loop tracer. The results show that the Al–Cr coating forms an overlapping structure and Al flakes lie nearly parallel to the substrate, which improves the anticorrosion and increases normal salt spray test from 10 to 100 h. The corrosion potential of NdFeB sintered magnets with and without the Al–Cr coating moves positively from −0.67 to −0.48 V, which is in accordance with Nyquist and Bode plots. The Al–Cr coating has little influence on the magnetic properties of the NdFeB sintered magnets.     

Synthesis and performance of Zn–Ni–P thin films

The electroplating of Zn–Ni–P thin film alloys from a sulfate bath containing phosphoric and phosphorous acid was investigated. The bath composition and the deposition parameters were optimized through Hull cell experiments, and the optimum experimental conditions were determined(p H = 2, temperature = 298–313 K, zinc sulfate concentration =30 g·L-1, EDTA concentration = 15 g·L-1, and current density = 1.0–2.0 A·dm-2). The SEM analysis of the coating deposited from the optimum bath revealed fine-grained deposits of the alloy in the presence of EDTA. Optical microscopy analysis indicated an electrodeposited thin film with uniform thickness and good adhesion to the steel substrate. The good adherence of the coatings was also demonstrated by the scratch tests that were performed, with a maximum determined value of 25 N for the critical load. Corrosion resistance tests revealed good protection of the steel substrate by the obtained Zn–Ni–P coatings, with values up to 85.89% for samples with Ni contents higher than 76%. The surface analysis of the thin film samples before and after corrosion was performed by X-ray photoelectron spectroscopy(XPS).     

An investigation on microstructural,spectral and magnetic properties of Pr–Cu double-substituted M-type Ba–Sr hexaferrites

This is first report on Pr–Cu double-substituted M-type Ba–Sr hexaferrites with nominal compositions Ba_0.3Sr_0.7−xPr_xFe_12.0−xCu_xO₁₉ (x = 0.00–0.35) fabricated by the solid-state reaction route. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM) and Hysteresis graph meter were used to characterize the synthesized M-type Ba–Sr hexaferrites. XRD results show that the hexaferrites with x ≤ 0.21 exhibited single M-type phase, while the hexaferrites with x ≥ 0.28 exhibited the M-type phase and impurity phases. FE-SEM images proposed that all particles with hexagonal platelet-like shape were homogeneously dispersed. The remanence (B_r) first increased with Pr–Cu content (x) from 0.00 to 0.14, and then decreased when x ≥ 0.14. The intrinsic coercivity (H_cj) and magnetic induction coercivity (H_cb) first decreased with x from 0.00 to 0.14, and then increased when x ≥ 0.14. Maximum energy product [(BH)_max] reached the maximum value at x = 0.14.