Effects of In-Process Ultrasonic Vibration on Weld Formation and Grain Size of Wire and Arc Additive Manufactured Parts.

Wire and arc additive manufacturing (WAAM) is a competitive technique, which enables the fabrication of medium and large metallic components. However, due to the presence of coarse columnar grains in the additively manufactured parts, the resultant mechanical properties will be reduced, which limits the application of WAAM processes in the engineering fields. Grain refinement and improved mechanical properties can be achieved by introducing ultrasonic vibration.

The inhibition effect of bank credits on PM concentrations: Spatial evidence from high-polluting firms in China.

Particulate Matter (PM) pollution in China has been a primary concern for public health in recent years, which requires banks to appropriately control their credit supply to industries with high pollution, high energy consumption, and surplus capacity. For this reason, this paper examines economic determinants of PM concentrations and incorporates the spatial spillover effect of bank credit by employing the spatial Durbin model (SDM) under the stochastic impacts by regression on population, affluence and technology framework. Using China's provincial dataset from 1998 to 2016, the main findings are as follows: First, there is evidence in support of spatial dependence of PM concentrations and their inverted U-shaped relationship with economic growth in China.

Diagnosis of cirrhotic portal hypertension and compensatory circulation using transsplenic portal scintigraphy with (99m)Tc-phytate.

Unlabelled: Our objective was to investigate the diagnostic value and clinical significance of transsplenic portal scintigraphy in cirrhotic portal hypertension and compensatory circulation.

Methods: Transsplenic portal scintigraphy, ultrasound, and gastroscopy were performed on 50 patients with cirrhotic portal hypertension and on 10 controls. According to the Child-Pugh classification, 15 patients with cirrhosis were Child A, 19 were Child B, and 16 were Child C.

Surfactant-assistant and facile synthesis of hollow ZnS nanospheres.

Small and monodisperse ZnS hollow nanospheres with outer diameter ranging from 60 to 70 nm and wall thickness of 15-20 nm were fabricated in a large scale by a simple surfactant polyethylene glycol (PEG) assisted method. The diameter and the wall thickness of the hollow nanospheres could be controlled by manipulating the amount of PEG and the aging time, respectively. Moreover, the wall of these hollow nanospheres is very compact.

Surfactant-assisted fabrication PbS nanorods, nanobelts, nanovelvet-flowers and dendritic nanostructures at lower temperature in aqueous solution.

PbS nanostructures with different morphologies, such as rod-like, belt-like, downy-velvet-flower-like and dendrite-like, were fabricated successfully under varied reaction conditions in aqueous solution at lower temperature by the assistance of surfactant CTAB. Especially, among all the synthesis methods for PbS nanocrystals, this is the first report using basic acetate of lead, which was formed at initial reaction stage, as a precursor to control the crystal nucleation rate. This synthesis method is a promising one to metal sulfide for its easy control, low-cost and large-scale production.

Preparation of uniform silica/polypyrrole core/shell microspheres and polypyrrole hollow microspheres by the template of modified silica particles using different modified agents.

Silica/polypyrrole (PPY) core/shell microspheres and PPY hollow microspheres were prepared by the template of silica particles whose surface character was modified with different modified agents. The morphology and structure of the particles were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Elemental analysis and X-ray photoelectron spectroscopy (XPS) were carried out to characterize the structure of PPY hollow microspheres.