Revisiting the Relationship Between Contract Governance and Contractors’ Opportunistic Behavior in Construction Projects

Contracts are crucial for curbing opportunism, a common phenomenon in construction projects. This article differentiates among the contractual mechanisms of obligatoriness, monitoring, and coordination, and studies the relationships between the complexity of the above functions and different types of opportunistic behavior. Using data from 262 clients (i.e., the parties issuing contracts) in the Chinese construction industry, this article reveals that contractual obligatoriness has a negative effect on strong-form opportunistic behavior. At the same time, contractual monitoring and coordination have positive and negative effects, respectively, on weak-form opportunistic behavior. Furthermore, we find that goodwill trust mediates contractual coordination's effect on weak-form opportunistic behavior. This article contributes to both the contract management literature and the interorganizational relationship governance literature by providing more nuanced findings that speak to the debate surrounding the relationship between contractual governance and opportunistic behavior, elaborate the mediation mechanism, and provide insights into the contractual function view. © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other work

Topological Weyl and Node-Line Semimetals in Ferromagnetic Vanadium-Phosphorous-Oxide β\beta-V2_2OPO4_4 Compound

We propose that the topological semimetal features can co-exist with ferromagnetic ground state in vanadium-phosphorous-oxide $\beta$-V$_2$OPO$_4$ compound from first-principles calculations. In this magnetic system with inversion symmetry, the direction of magnetization is able to manipulate the symmetric protected band structures from a node-line type to a Weyl one in the presence of spin-orbital-coupling. The node-line semimetal phase is protected by the mirror symmetry with the reflection-invariant plane perpendicular to magnetic order. Within mirror symmetry breaking due to the magnetization along other directions, the gapless node-line loop will degenerate to only one pair of Weyl points protected by the rotational symmetry along the magnetic axis, which are largely separated in momentum space. Such Weyl semimetal phase provides a nice candidate with the minimum number of Weyl points in a condensed matter system. The results of surface band calculations confirm the non-trivial topology of this proposed compound. This findings provide a realistic candidate for the investigation of topological semimetals with time-reversal symmetry breaking, particularly towards the realization of quantum anomalous Hall effect in Weyl semimetals.Comment: 5 pages, 4 figure

Study on the mechanism of cobalt recovery from waste lithium cobaltate batteries in citric acid system

The waste lithium cobalt acid batteries were utilized as raw materials to separate out LiCoO2 cathode material. Citric acid was used to leach cathode material, and LiCoO2 leaching solution was electrodeposited to obtain cobalt plating, in the meantime the Li2+ ions were enriched. The optimized conditions of leaching process are 1,2 mol/L citric concentration and 0,35 mol/L sodium thiosulfate concertation, the leaching efficiency of cobalt and lithium is 97,5 % and 97,0 % respectively. At pH 4, the smooth cobalt coating with fine grains can be obtained on the surface of the stainless-steel cathode

Study on the mechanism of cobalt recovery from waste lithium cobaltate batteries in citric acid system

The waste lithium cobalt acid batteries were utilized as raw materials to separate out LiCoO2 cathode material. Citric acid was used to leach cathode material, and LiCoO2 leaching solution was electrodeposited to obtain cobalt plating, in the meantime the Li2+ ions were enriched. The optimized conditions of leaching process are 1,2 mol/L citric concentration and 0,35 mol/L sodium thiosulfate concertation, the leaching efficiency of cobalt and lithium is 97,5 % and 97,0 % respectively. At pH 4, the smooth cobalt coating with fine grains can be obtained on the surface of the stainless-steel cathode