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The purpose of this paper is to design a very low‐noise transimpedance amplifier (TIA) for a novel multi‐pixel CMOS photon detector which performs secondary electron (SE) detection in the scanning electron microscope (SEM).

The TIA, which is implemented with three‐stage push‐pull inverters, is optimised using a nomograph technique developed in MATLAB. SPICE simulations are conducted to verify the results generated from MATLAB. Important performance figures are obtained experimentally and these measurements are compared with simulation results.

A low‐noise TIA fabricated in a standard 0.35 μm CMOS technology was tested. Experimental results obtained show that the TIA connected to a photodiode with a junction capacitance of 0.8 pF can carry out its task effectively with a transimpedance gain of 126.9 dBΩ, a bandwidth of 9.8 MHz, an input‐referred noise of 2.50×10⁻¹³ A/√Hz and an SNR of 12.8. The power consumption of the TIA was 49.3 mW. These encouraging results have exhibited the potential of the circuit for use in the CMOS photon detector.

This paper presents a low‐noise transimpedance amplifier that is highly suitable to be used as a critical constituent block for the CMOS photon detector which aims to take over the role of photomultiplier tube in SE detection in the SEM. Solid‐state approaches have recently been reinvigorated for improving certain aspects of SE detection in scanning electron microscopy and this work has supported and contributed to the trend.

The purpose of this paper is to compare a picture obtained by means of electron microscopy, resulting from the interaction of an electron beam with the material surface, and the numerical mapping of the material surface potentials. This new method has been successfully applied to a composite material and will be checked to describe other complex materials.

This surface potential function is calculated by a numerical approximation of Laplace's equation with three variables reduced to two variables by using the continuity assumptions on the potential.

The results are particularly satisfactory and allow future developments in electron microscopy picture analysis to be forecasted.

This paper demonstrates new approximated operator of the surface potential with good accordance between experimental and calculated values.

This paper aims to investigate the efficacy of grape pomace extract (GPE) as an eco-friendly vapor phase green inhibitor for corrosion of steel and assess the effect of the major compounds of extract on the inhibition efficiency.

The present study was carried out to identify the components present in the 2-propanol GPE by gas chromatography–mass spectrometry (GC-MS) analysis. Gravimetric, electrochemical impedance spectroscopy, potentiodynamic polarization, scanning electron microscopy and FTIR techniques were used to study the corrosion inhibitive.

GPE has inhibited mild steel corrosion in conditions of periodic condensation of moisture. The gravimetric measurement indicates that inhibition efficiency shows direct proportional relation with concentration of inhibitor. The GPE and main components acted as a mixed-type inhibitor with predominant cathodic effectiveness. Research limitations/implications. Because of the presence of large number of compounds in the extract, it becomes difficult to understand the most active compound responsible for inhibition. However, from gas chromatography, mass spectrometry and quantum data, the assumption has been made that the major compound of GPE is responsible for the inhibition activity.

The extract can be used in the temporary corrosion protection and is designed to prevent the corrosion of metal surfaces of equipment during transportation and storage.

GPE can be used as a potential source of ecofriendly corrosion inhibitor for steel corrosion.

The purpose of this paper is to improve the efficiency of dye-sensitized solar cells (DSSCs) which present promising low-cost alternative to the conventional silicon solar cells mainly due to comparatively low manufacturing cost, ease of fabrication and relatively good efficiency. One of the undesirable factor in DSSCs is the electron recombination process that takes place at the transparent conductive oxide/electrolyte interface, on the side of photoelectrode. To reduce this effect in the structure of the solar cell, a TiO₂ blocking layer (BL) by atomic layer deposition (ALD) was deposited.

Scanning electron microscope, Raman and UV-Vis spectroscopy were used to evaluate the influence of BL on the photovoltaic properties. Electrical parameters of manufactured DSSCs with and without BL were characterized by measurements of current-voltage characteristics under standard AM 1.5 radiation.

The TiO₂ BL prevents the physical contact of fluorine-doped tin oxide (FTO) and the electrolyte and leads to increase in the cell’s overall efficiency, from 5.15 to 6.18%. Higher density of the BL, together with larger contact area and improved adherence between the TiO₂ layer and FTO surface provide more electron pathways from TiO₂ to FTO which facilitates electron transfer.

This paper demonstrates that the introduction of a BL into the photovoltaic device structure is an important step in technology of DSSCs to improve its efficiency. Moreover, the ALD is a powerful technique which allows for the highly reproducible growth of pinhole-free thin films with excellent thickness accuracy and conformality at low temperature.

Nature and occurrence of food-borne pathogens in raw and processed food products evolved greatly in the past few years due to new modes of transmission and resistance build-up against sundry micro-/macro-environmental conditions. Assurance of food health and safety thus gained immense importance, for which bio-sensing technology proved very promising in the detection and quantification of food-borne pathogens. Considering the importance, different studies have been performed, and different biosensors have been developed. This study aims to summarize the different biosensors used for the deduction of food-borne pathogens.

The present review highlights different biosensors developed apropos to food matrices, factors governing their selection, their potential and applicability. The paper discusses some related key challenges and constraints and also focuses on the needs and future research prospects in this field.

The shift in consumers’ and industries’ perceptions directed the further approach to achieve portable, user and environmental friendly biosensing techniques. Despite of these developments, it was still observed that the comparison among the different biosensors and their categories proved tedious on a single platform; since the food matrices tested, pathogen detected or diagnosed, time of detection, etc., varied greatly and very few products have been commercially launched. Conclusively, a challenge lies in front of food scientists and researchers to maintain pace and develop techniques for efficiently catering to the needs of the food industry.

Biosensors deduction limit varied with the food matrix, type of organism, material of biosensors’ surface, etc. The food matrix itself consists of complex substances, and various types of food are available in nature. Considering the diversity of food there is a need to develop a universal biosensor that can be used for all the food matrices for a pathogen. Further research is needed to develop a pathogen-specific biosensor that can be used for all the food products that may have accuracy to eliminate the traditional method of deduction.

The present paper summarized and categorized the different types of biosensors developed for food-borne pathogens.

The purpose of this paper is to research the induced flashover laws of different insulation materials under electrostatic electromagnetic pulse, and the induced flashover characteristics of different electrode structures are further explored.

According to standard IEC 61000–4-2, an experimental system of electrostatic electromagnetic pulse flashover for insulation materials is established. The induction flashover laws of polytetrafluoroethylene, epoxy resin and polymethyl methacrylate surface-mounted finger electrodes under the different intensity of electrostatic electromagnetic pulse are researched. The influence of the finger electrode, needle–needle electrode and needle–plate electrode on insulation flashover was compared. Secondary electron emission avalanche (SEEA) and field superposition theory are used to analyze the experimental results of electrostatic electromagnetic pulse induced flashover.

The larger the dielectric strength of insulation materials, the more difficult flashover occurs on the surface. The field superposition enhances collision ionization between electrons and gas molecules, which leads to the insulation materials surface induced flashover easily by electrostatic electromagnetic pulse. The sharper the electrode shapes on the insulation materials surface, the stronger the electric field intensity at the cathode triple junction, more initial electrons are excited to form the discharge channel, which easily leads to flashover on the surface of the insulating material.

The proposed field superposition combined with the SEEA method provides a new study perspective and enables a more rational, comprehensive analysis of electrostatic electromagnetic pulse induced flashover of insulation materials. The work of this paper can provide a reference for the safety protection of spacecraft in orbit under a strong electromagnetic field environment, increase the service life of spacecraft and improve the reliability of spacecraft’s safe operation in orbit. It provides a basis for the selection of insulation materials for equipment under the different intensities of the external electromagnetic environment.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

The examination of products of aqueous and non aqueous corrosion is carried out to obtain information about one of a combination of aspects such as composition, hardness, stress level, adhesion to basis metal and other mechanical properties (figure 1). A number of techniques are avialable to investigate corrosion products and some of these techniques have found greater application with products of aqueous corrosion and some with products of gaseous corrosion. This paper presents the technqiues available for obtaining information about the various aspects mentioned above and discusses the main characteristics, nature of data obtainable, advantages and limitations of some of the less know techniques.