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An overview of Sun–Sky Radiometer Observation Network (SONET) measurements in China is presented. Based on observations at 16 distributed SONET sites in China, atmospheric aerosol parameters are acquired via standardization processes of operational measurement, maintenance, calibration, inversion, and quality control implemented since 2010. A climatology study is performed focusing on total columnar atmospheric aerosol characteristics, including optical (aerosol optical depth, ÅngstrÖm exponent, fine-mode fraction, single-scattering albedo), physical (volume particle size distribution), chemical composition (black carbon; brown carbon; fine-mode scattering component, coarse-mode component; and aerosol water), and radiative properties (aerosol radiative forcing and efficiency). Data analyses show that aerosol optical depth is low in the west but high in the east of China. Aerosol composition also shows significant spatial and temporal variations, leading to noticeable diversities in optical and physical property patterns. In west and north China, aerosols are generally affected by dust particles, while monsoon climate and human activities impose remarkable influences on aerosols in east and south China. Aerosols in China exhibit strong light-scattering capability and result in significant radiative cooling effects.

Underground pipeline is an important part of urban infrastructure, known as the “lifeline” of the city. At present, there are many incomplete data of urban ground line pipelines, only part of the data is not high precision or inconsistent with the status quo, which is easy to cause serious accidents in the construction of underground pipelines often cut or damaged, so it is particularly important to establish a reliable underground pipeline database as soon as possible. Pipeline detectors currently occupy tens of thousands of units in the market, and the annual growth rate of 20%∼30%. At present, the positioning error (sounding error) of pipeline detector is faced with the problem of undetermined and untraceable. The relevant calibration device established in this paper can provide reliable data and provide strong guarantee for the data of pipeline detector.

The aim of this study was to clarify the role of TCF19 in influencing the malignant progression of colorectal cancer (CRC) by negatively regulating WWC1.Relative expression levels of TCF19 and WWC1 in CRC tissues and cells were detected by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). The prognosis of CRC patients was assessed by the Kaplan-Meier method. Meanwhile, the correlation between TCF19 and pathological indexes of CRC patients was evaluated. Regulatory effects of TCF19/WWC1 on viability, colony formation ability, and migration in HT29 and HCT-8 cells were evaluated. Finally, rescue experiments were conducted to elucidate a negative feedback loop of TCF19/WWC1 in influencing the progression of CRC.TCF19 was significantly up-regulated in CRC, while WWC1 was down-regulated. High-level TCF19 or low-level WWC1 indicated worse survival of CRC patients. Besides, TCF19 expression level was positively correlated with the occurrence of distant metastasis in CRC. Silence of TCF19 significantly attenuated proliferative and migratory capacities of HT29 cells. However, overexpression of TCF19 yielded the opposite trends in HCT-8 cells. WWC1 expression was negatively regulated by TCF19 in CRC tissues. In addition, knockdown of WWC1 abolished the regulatory effect of TCF19 on CRC cells.TCF19 is closely correlated with the occurrence of distant metastasis and poor prognosis of CRC. Furthermore, it aggravates the malignant progression of CRC via negatively regulating WWC1.

Recent levels of structural integrity of components built in the Aeroswift high-speed laser powder bed fusion machine have led to the decision to produce a structural aircraft component through this technology. The Aeroswift machine is capable of building larger Ti6Al4V parts at a more rapid pace than current commercial laser metal powder bed fusion systems. As prototype component, the nose-wheel fork of the AHRLAC aircraft, which was conventionally machined in aluminum alloy 7050, was selected. This paper describes the design, topology optimisation and the manufacturing approach taken in this project. Given the design space, loads, strength requirements and boundary conditions prescribed by the AHRLAC engineers, topology optimisation was performed on the nose-wheel fork to design a lightweight component for production in Ti6Al4V. Different topology optimisation software suites were used, to establish their capabilities and fit-for-purpose features. The optimised design and percentage of weight saving are presented. An assessment based on the experience with the different software suites is offered.

Although many cases of medical implants produced through additive manufacturing (AM) in Ti6Al4V have been reported in literature, most of these processes had not been qualified. To enable certification and commercialisation of medical implants and devices an ISO 13485:2016 quality management system was successfully implemented in the Centre for Rapid Prototyping and Manufacturing (CRPM) at the Central University of Technology, Free State in South Africa. This certification covers qualification of both design, development and production of patient specific custom made titanium implants, as well as preoperative models, jigs and cutting guides in nylon by means of AM and supports commercialisation. With this quality management system as framework for ensuring the reliability and repeatability of the AM performed at the CRPM, the generation of data to validate the individual processes in the AM process chain was pursued. Sufficient research data has been produced and published to prove that medical implants produced through AM can fully comply with the international standards for material, physical, chemical and mechanical properties. In this paper the research performed towards the qualification of AM of Ti6Al4V medical implants is discussed. Examples are given of internationally leading work on utilising these implants in maxillofacial and orthopaedic surgeries.

This paper states the importance of determining the muzzle leaving time of guns with a high degree of accuracy. Two commonly used methods are introduced, which are the high speed photography method and photoelectric transducer method, and the advantage and disadvantage of these two methods are analyzed. Furthermore, a new method to determine the muzzle leaving time of guns based on the combination of high speed photography and synchronized trigger technology is present in this paper, and its principle and uncertainty of measurement are evaluated. The firing experiments shows that the present method has distinguish advantage in accuracy and reliability from other methods.

SUMMARY A method is described which can be used for rapid in situ determinations of relative foil thicknesses in a transmission electron microscope, and is illustrated for the case of aluminium. A calibration curve for the foil thickness determination was obtained by measuring the relative transmission of electrons through standard thickness foils which were prepared and measured outside the electron microscope. By using this calibration curve, it was merely necessary to measure the relative transmission of electrons through an unknown specimen in order to determine its thickness.