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This paper aimed to prepare a kind of ZnS nanoparticles/poly(phenylene vinylene) (PPV) nanofibre and investigate its properties. Because the ZnS nanoparticles are important optoelectronic materials, their incorporation into one-dimensional (1D) nanoscale polymer matrices should be a meaningful subject for electrospinning.

ZnS/PPV composite nanofibres with an average diameter of 600 nm were successfully prepared by a combination of the in situ method and electrospinning technique. The nanofibres were electrospun from Zn(CH3COO)2·2H2O and PPV precursor composite solution, and the ZnS/PPV fibres were obtained by exposure of the electrospun fibres to H₂S gas to prepare ZnS nanoparticles in situ. Such fibres were characterised using X-ray Diffraction (XRD), Fourier transform infrared, transmission electron microscope (TEM), scanning electron microscope and photoluminescence (PL). The photoelectric properties of the fibres obtained were also investigated.

XRD patterns proved that ZnS nanocrystals generated in the composite nanofibres. The TEM image showed that the nanocrystals were homogeneously dispersed in the nanofibres. The PL spectrum of ZnS/PPV composite nanofibres exhibited a blue shift relative to the PPV nanofibres. I-V curve of the single nanofibre device under 5.76 mW/cm2 light illumination showed that the composite nanofibres have good photoelectric properties.

The comparisons of advantages between ZnS/PPV nanofibres with similar nanofibres will be further expanded in a later research.

Results demonstrate the promise of these novel nanostructures as ultraminiature photodetectors with the potential for integration into future hybrid nanophotonic devices and systems.

The integration of inorganic semiconductor nanoparticles into organic conjugated polymers leads to composite materials with unique physical properties and important application potential. In this work, ZnS nanoparticles were introduced into PPV by an in situ method, so as to obtain a kind of novel 1D nanomaterials with good photoelectric properties.

The purpose of this paper is to analyze the measurement error of a three-dimensional coordinate measurement system based on dual-position-sensitive detector (PSD) under different background light.

The mind evolutionary algorithm (MEA)-back propagation (BP) neural network is used to predict the three-dimensional coordinates of the points, and the influence of the background light on the measurement accuracy of the three-dimensional coordinates based on PSD is obtained.

The influence of the background light on the measurement accuracy of the system is quantitatively calculated. The background light has a significant influence on the prediction accuracy of the three-dimensional coordinate measurement system. The optical method, electrical method and photoelectric compensation method are proposed to improve the measurement accuracy.

BP neural network based on MEA is applied to the coordinate prediction of the three-dimensional coordinate measurement system based on dual-PSD, and the influence of background light on the measurement accuracy is quantitatively analyzed.

The purpose of this paper is to improve photoelectric detection target (PDT) optical detection performance and detection view, by analyzing its influence factors and putting forward a new method to design its optical detection system.

Using rectangle linked photoelectric detector, with low noise and high response, to design optical detection system and gain faint projectile image information; bringing forward a deviating focusing technique to eliminate detection blind area of photoelectric detector; and designing adjustable slit diaphragm to weaken background light influence.

The results of experimentation in shooting range show that the new PDT has improved detection sensitivity and performance.

The paper presents a new design method in photoelectric detection target (PDT) optical detection system, which can provide a new method to design fire across measurement system and gain accurate projectile's coordinates data in the shooting range.

This study aims to investigate photosensing characteristics of SiC and GaN nanowire-based devices through exposure to UV light. The photocurrent transients have been modeled to determine rise and decay process time constants. The 1D-semiconductor nanowires can exhibit higher light sensitivity compared to bulk materials because of their large surface area to volume ratio and the quantum size effects.

Nanowire devices have been fabricated through dielectrophoresis for integrating nanowires onto pre-patterned electrodes (10 nm Ti/ 90 nm Au) with a spacing about 3 µm onto SiO₂/Si (doped) substrate. The photocurrent measurements were carried out under room temperature conditions with UV light of 254 nm wavelength.

SiCNWs yield very short rise and decay time constants of 1.3 and 2.35 s, respectively. This fast response indicates an enhanced surface recombination of photoexcited electron-hole pairs. Conversely, GaNNWs yield longer rise and decay time constants of 10.3 and 15.4 s, respectively. This persistent photocurrent suggests a reduced surface recombination process for the GaNNWs.

High selective UV light sensitivity, small size, very short response time, low power consumption and high efficiency are the most important features of nanowire-based devices for new and superior applications in photodetectors, photovoltaics, optical switches, image sensors and biological and chemical sensing.

The purpose of this paper is to evaluate the detection performance of infrared photoelectric detection system and establish stable tracking platform.

This paper puts forward making use of the finite element analysis method to set up the infrared radiation characteristics calculation model of flying target in infrared photoelectric detection system; researches the target optical characteristics based on the target imaging detection theory; sets up the heat balance equation of target’s surface node and gives the calculation method of total radiation intensity of flying target; and deduces the target detection distance calculation function; studies the changed regulation of radiation energy that charge coupled device (CCD) gain comes from target surface infrared heat radiations under different sky background luminance and different target flight attitude.

Through calculation and experiment analysis, the results show that when the target’s surface area increases or the target flight velocity is higher, the radiation energy that CCD obtained is higher, which is advantageous to the target stable detection in infrared photoelectric detection system.

This paper uses the finite element analysis method to set up the infrared radiation characteristics calculation model of flying target and give the calculation and experiment results; those results can provide some data and improve the design method of infrared photoelectric detection system, and it is of value.

MANY problems associated with aircraft investigations involve the accurate measurement of fluctuating fluid pressures. Various types of pickup exist from which choice may be made for this purpose. The suitability of a particular type for a specific application depends on the characteristics of the type and its associated electronic recorder. The fundamental requirements of fluctuating pressure pickups are discussed, and various types are described and typical examples of their application are given. Design data are derived based on experiments conducted on condenser type pickups, from which it is possible to design single diaphragm types for particular frequency and sensitivity requirements.

The use of industrial robots in the advanced countries of the world is growing. Whilst generally the concept of a robot is taken as a highly versatile human‐like device the term also extends to include much simpler devices of the pick‐and‐place type with a fixed sequence of events and these form by far the largest proportion of the world's robot population. Whilst they lack versatility in themselves they often form part of a much more complex automatic system in which some degree of flexibility is required. In addition they must operate at their optimum rate whilst being fail‐safe in operation. The design of a suitable control system to meet such demands particularly when a number of such devices and the primary process machinery have to be interlinked can be solved with the aid of sequential switching theory.

The purpose of this paper is to demonstrate the influence of annealing treatment on the photovoltaic properties of the solar cell based on ITO/PEDOT:PSS/ZnO:P3HT/Ag.

The influence of the annealing temperature and time on the P3HT/ZnO interface morphology and the ITO/PEDOT:PSS/ZnO:P3HT/Ag solar cell performance was discussed. The morphology and the current‐voltage (J‐V) characteristics were investigated by atomic force morphology (AFM) and solar simulator with an AM 1.5 G filter under an irradiation intensity of 100 mW cm⁻². The light intensity was calibrated using a standard silicon photovoltaic solar cell.

The photovoltaic performances were found to have been greatly enhanced by an annealing treatment at 145°C for 30 min.

The paper demonstrates that the annealing treatments play a crucial role in improving the morphology and J‐V performance of the ITO/PEDOT:PSS/ZnO:P3HT/Ag solar cell.

AN interesting comment from the Salisbury and South Wilts team of industrialists who put the first Local Productivity Council Circuit Scheme into operation in their area suggests that this scheme may prove invaluable in awakening general interest in, and in giving practical impetus to, increased productivity at all levels.

New Conductor Composition Reduces Firing Time by Half Du Pont has introduced a new palladium‐silver conductor composition which, with a firing cycle of only 15–30 minutes, instead of the usual 60 minutes, meets the requirements of hybrid circuit manufacturers for a material with fast‐processing characteristics.