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Since the industrial revolution, greenhouse gas emissions caused by human activities have posed an unprecedented global challenge to social development and impact on the natural environment. With the growing awareness of environmental protection and the promotion of international cooperation mechanisms, there is a global consensus to control greenhouse gases. In order to avoid irreversible and catastrophic climate change, there is an urgent need for more companies to take action and make credible commitments to combat climate change and carbon reduction goals aligned with the Paris Agreement and the UN Sustainable Development Goals. As one of the largest and most influential international food and beverage companies with a range of well-known brands, PepsiCo has made ambitious commitments to science-based climate goals, including reducing GHG emissions from its direct operations by 75% against the 2015 baseline and reducing GHG emissions across its indirect value chain by 40% by 2030, as well as setting an ambitious new target to achieve net-zero emissions by 2040. PepsiCo has incorporated carbon reduction and climate strategies in all focus areas across its value chain, accelerating its work on broadening the scale of sustainable agriculture and regenerative farming practice; reducing plastic use and increasing the use of recycle and renewable materials as well as adopting low-carbon alternatives; developing efficient and alternative solutions in transportation and distribution; shifting to renewable electricity and fuels in manufacturing and fleet. Up to 2021, PepsiCo has achieved a 23% of the absolute emissions target of reducing Scope 1 and Scope 2 emissions and 7.9% of the absolute emissions target of reducing Scope 3 emissions. This research aims to evaluate the performance of PepsiCo on achieving their carbon reduction targets based on the analysis of the reported carbon estimates and reduction strategies, and also provides future strategic suggestions and guidance by adopting case study analysis. Although PepsiCo has reported great progress in reducing carbon emissions, further efforts are needed to achieve these goals.

Carbon nanotube (CNT) buckypapers, or films, have the potential for wide applications because of their unique properties. Neat buckypapers or pristine CNT (PCNT) films have relatively large elongation but low strength and low modulus due to the weak interaction between CNTs. Chemical modifications of PCNT films can significantly strengthen the interaction between CNTs, resulting in high strength and high modulus but usually accompanied by low elongation. Here, we report the functionalization of pristine CNT films by thiol-ended hyperbranched polymers (THBP-n) via a thiol-ene click reaction that can introduce simultaneous improvements on the strength, modulus, and elongation to the PCNT film by 689, 812, and 32.4%, respectively. The high thiol content of THBP-n enables the formation of a network with a high degree of cross-linking between carbon nanotubes, which provides high-efficiency load transfer that increases the tensile strength and modulus of the resulting films and at the same time a compressible hyperbranched structure that allows for deformation and slip between CNTs and consequently improved elongation. The main factors affecting the mechanical performance of the functionalized CNT film are also investigated.

Preparation of carbon nanotube (CNT) films with both high strength and high elongation is a key challenge to wide application of CNT. A simple method has been investigated to design and prepare high strength and elongation CNT films. This was achieved using a thiol-ene click reaction between the double bond groups of the CNT films and the thiol groups of mercaptans. The effects of mercaptans contents in the functionalized CNT film, click reaction time and the ratio between mercaptans and CNT film on their mechanical strength have been researched. The tensile strength of the functionalized CNT film was 560% higher than that of the prime CNT film. The improvement and functionalized mechanism of CNT film were studied by scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and Fourier transform infrared spectroscopy. Compared with prime carbon nanotube films, the inter-tube interaction of the functionalized CNT films has been changed from weaker van der Waals force to stronger chemical bond, and the cross-link network of mercaptans chain connected CNTs also enhances the load transfer among the CNTs and reduces the distance of the interfacial slippage, which contributes to the improved mechanical properties. This method about improving strength of CNT films will supply a new strategy for preparing high strength CNT film.

The fuel-consumption and emissions from transportation present severe challenges to the human environment. This article proposes a novel approach of space-time path supported estimation for vehicles' fuel-consumption and emissions. In the proposed approach,space-time paths of vehicles are built under space-time integrated 3-dimensions coordinate firstly and mobile activities (MA) and stationary activities (SA) are extracted from these space-time paths. Then the approach estimates the fuel-consumption and emissions from each Space-Time Path Segment (STPS) and the moving parameters with COPERT model. Finally this article presents an N-Dimensional model for visualizing the moving characteristics,fuel-consumption and emissions of each STPS in an integrated frame. In the case study,fuel-consumption and emissions of a single vehicle and an area of road network are estimated and analyzed using GPS trace data. The results show that the space-time path supported approach is superior to the traditional average speed based approach in the aspects of precision and visualization. The proposed fuel-consumption and emissions estimating approach is effective in energy and emissions information acquisition.