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Abstract Jet electrochemical (Jet-EC) milling, using a movable nozzle as the cathode, can fabricate complicated structures flexibly. With the dissolution restricted to a limited area by the electrolyte jet, high removal localization and good surface quality can be obtained. However, the edge of the machined groove is usually subject to stray corrosion because of the low current density in the edge area. In this paper, it is confirmed that the jet shape, which is determined by the working parameters, has a notable influence on the edge condition. Through experiments and analysis, the interrelation between the working parameters, jet shape and edge condition in Jet-EC groove milling is established. It is found that the stray corrosion on the edge can be reduced significantly by adjusting the jet shape, and the necessary conditions to completely eliminate the stray corrosion are established. Furthermore, based on the conclusions, a groove with both a sharp edge and a smooth surface is fabricated via a two-pass process. A deep groove (1.208 mm) with a sharp edge is produced via multiple-pass milling with downward cathode feeding. [ABSTRACT FROM AUTHOR]

Electrochemical drilling (ECD) is a useful method to produce small holes with a large aspect ratio on hard-to-machine materials. Recently, instead of using an acid electrolyte, more and more research has focused on neutral salt electrolytes because they are less harmful to the environment. However, more problems have been caused to the removal of waste products, especially in deep-hole drilling. Traditionally, an electrolyte flow with constant pressure control is adopted in ECD, which might result in the poor removal of waste products at depth because of pressure loss. In this paper, an ECD method with a constant electrolyte flow has been proposed to obtain a consistent ability to remove insoluble waste products from machining gap. Experiments of ECD with both constant electrolyte pressure and constant flow are conducted on workpieces of Inconel 718. Machining currents and the profile of machined holes are compared between the two methods. The results show that when a constant electrolyte flow rate is applied, the machining currents are much smoother and the profile of machined holes is also uniform. In addition, the pressure variation in the constant flow method increases linearly with machining depth. ECD with a constant flow also has an increased feed rate. [ABSTRACT FROM AUTHOR]

Abstract: A comparative study of prestressed continuous steel–concrete composite beams is carried out based on an experimental investigation. Four full-scale continuous composite beams were tested, among which two were two-span beams and two were three-span beams. One of the two-span beams was a conventional non-prestressed composite beam, and the other was a composite beam prestressed with external tendons in both the positive and negative moment regions. One of the three-span composite beams was non-prestressed, and the other was prestressed only in the negative moment regions with external high-strength tendons. The cracking behaviors, distortional lateral and local buckling as well as the load carrying capacity of the beams were investigated experimentally. Full plasticity was developed at the mid-span section of each beam; however, the maximum moments attained at the internal supports were governed by local buckling, which is related to the slenderness of the composite section. It is found that in hogging moment regions, the ultimate moment resistance of a composite beam prestressed with external tendons is governed by either distortional lateral buckling or local buckling, or an interactive mode composed of distortional lateral and local buckling. The results show that exerting prestressing on a continuous composite beam with external tendons increases the degree of the internal force and moment redistribution in the beam. A design proposal based on moment redistribution to evaluate the load carrying capacity of continuous composite beams with external tendons is proposed. [Copyright &y& Elsevier]

The AGCU Expressmarker 20 + 20Y Kit is a newly devised short tandem repeat (STR) multiplex system that simultaneously analyses a set of 19 autosomal STR loci, 20 Y chromosomal STR loci and the amelogenin locus with six-dye fluorescent labelling. Here, the AGCU Expressmarker 20 + 20Y system was validated following the guidelines published by the Scientific Working Group on DNA Analysis Methods (SWGDAM), including PCR-condition, sensitivity, mixtures, species specificity, models of inhibition, precision, stutter percentage, concordance, population genetic studies, performance on three kinds of degraded DNA and a type of casework samples. The results indicated that the kit had high sensitivity when there was a small amount of DNA (0.0625 ng), more than one male (minor: major=1:19), or a mixture of males and females (male: female=1:32), models of inhibition (250 μM hematin, 1500 ng/μL humic acid and more than 100 ng/μL tannic acid) and degraded samples. The kit showed high precision level with standard deviation of allele size no more than 0.0930. Furthermore, this system was also tested in 444 random male samples of Chinese Han and Hui population, showing its high discrimination capability in Han and Hui population. Meanwhile, the system was applicable to the case of the AMELY abnormality. In short, the kit was verified and proved to be a robust, reliable and suitable tool for human identification and casework samples. [ABSTRACT FROM AUTHOR]

• Microwave is best treatment on transglutaminase (TGase)-induced whey protein isolate. • Ultrasound-microwave promoted the reaction of whey protein isolate and TGase. • Ultrasound-microwave enhanced properties of TGase-induced whey protein isolate. In the present study, ultrasound (400 W, U), microwave heating (75 ℃ for 15 min, M) and ultrasound synergized with microwave heating (UM) pretreatments of whey protein isolate (WPI) were applied to investigate and compare their influence on structure, physicochemical and functional characteristic of transglutaminase (TGase)-induced WPI. From the results of size exclusion chromatography, it could be seen that all three physical pretreatments could promote the formation of polymers in TGase cross-linked WPI, whose polymer amounts were increased by the order of U, UM and M pretreatment. Among three physical methods, M pretreatment had the strongest effect on structure and functional characteristics of TGase-induced WPI. Furthermore, compared with TGase-induced WPI, α-helix and β-turn of M−treated TGase-induced WPI (M−WPI−TGase) were reduced by 7.86% and 2.93%, whereas its β-sheet and irregular curl were increased by 15.37% and 7.23%. Zeta potential, emulsion stability and foaming stability of M−WPI−TGase were increased by 7.8%, 59.27% and 28.95%, respectively. This experiment exhibited that M was a more effective pretreatment method than U, UM for WPI, which could promote its reaction with TGase and improve its functional properties. [ABSTRACT FROM AUTHOR]