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In this study, a viscosity-reducing polycarboxylic acid superplasticizer (VRPCE) was synthesized using methylallyl polyoxyethylene ether (HPEG), acrylic acid (AA), and maltodextrin maleic acid monoester (MDMA) as the main raw materials. The influences of the VRPCE on the microscopic properties of cement paste were studied by gel permeation chromatography (GPC), total organic carbon test (TOC), zeta potential, laser particle size analysis, XRD, MIP, TG, and SEM. Finally, the effects of the VRPCE on the macroscopic properties of cement mortar were evaluated through flow time, slump flow, compressive strength, shrinkage, and creep. The results showed that the VRPCE can improve the hydration degree of the cement, optimize the pore structure, increase the porosity, improve the fluidity, compressive strength, and creep, and decrease the shrinkage resistance of the cement mortar.

Search engine marketing (SEM) is an important channel for the success of e-commerce. With the increasing scale of catalog items, designing an efficient modern industrial-level bidding system usually requires overcoming the following hurdles: 1. the relevant bidding features are of high sparsity, preventing an accurate prediction of the performances of many ads. 2. the large volume of bidding requests induces a significant computation burden to offline and online serving. In this article, we introduce an end-to-end structure of a multi-objective bidding system for search engine marketing for Walmart e-commerce, which successfully handles tens of millions of bids each day. The system deals with multiple business demands by constructing an optimization model targeting a mixture of metrics. Moreover, the system extracts the vector representations of ads via the Transformer model. It leverages their geometric relation to building collaborative bidding predictions via clustering to address performance features' sparsity issues. We provide theoretical and numerical analyzes to discuss how we find the proposed system as a production-efficient solution.