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Environmental and resilience are currently vital concerns when managing Supply Chains (SC). Doing so in a competitive setting, with diverse stakeholders' perspectives and dealing with unforeseen disruptive events is challenging. Today, this is a reality where, with the actual COVID-19 pandemic, supply chains face reduced demand and stoppages at different levels, calling for the urgent need to invest in designing and planning resilient SC. But resilience must not leave apart other vital goals as is the environmental goal, which nowadays requires special attention. This is especially critical in the process industries where environmental concerns are often at stake. We address this challenge in the current work by representing the cost associated with CO2 emissions, considering the EU emissions trading system (EU ETS). This system makes the cost associated with emissions a variable value attributed by the market. A Mixed Integer Linear Programming model (MILP) is here presented which allows to understand the supply chain resilience of different supply chain structures. This is done with the objective of maximising the Expected Net Present Value (ENPV) while facing disruptions, and the presence of uncertainty in demand is considered. The results show that our model can help decision-makers to create resilient SC with good environmental behaviour and without compromising financial results. © 2021 Elsevier B.V.

Nitric oxide (NO) presents innumerable biological roles, and its exogenous supplementation for therapeutic purposes has become a necessity. Some nanoporous materials proved to be potential vehicles for NO with high storage capacity. However, there is still a lack of information about their efficiency to release controlled NO and if they are biocompatible and biologically stable. In this work, we address this knowledge gap starting by evaluating the NO release and stability under biological conditions and their toxicity with primary keratinocyte cells. Titanosilicates (ETS-4 and ETS-10 types) and clay-based materials were the materials under study, which have shown in previous studies suitable NO gas adsorption/release rates. ETS-4 proved to be the most promising material, combining good biocompatibility at 180 μg/mL, stability and slower NO release. ETS-10 and ETAS-10 showed the best biocompatibility at the same concentration and, in the case of clay-based materials, CoOS is the least toxic of those tested and the one that releases the highest NO amount. The potentiality of these new NO donors to regulate biological functions was assessed next by controlling the mitochondrial respiration and the cell migration. NO-loaded ETS-4 regulates O2 consumption and cell migration in a dose-dependent manner. For cell migration, a biphasic effect was observed in a narrow range of ETS-4 concentration, with a stimulatory effect becoming inhibitory just by doubling ETS-4 concentration. For the other materials, no effective regulation was achieved, which highlights the relevance of the new assessment presented in this work for nanoporous NO carriers that will pave the way for further developments.

[EN] Strategic polyoxometalate Keggin-type structural modification was performed to increase the oxidative catalytic performance to desulfurize model and real diesels. The most active lacunar structure [PWO] (PW) showed to complete desulfurize a simulated diesel after 60 min at 70 °C. Its application as homogeneous catalyst using a biphasic system 1:1 diesel/acetonitrile needed to use an excess of oxidant (ratio HO/S = 8). The immobilization of the PW on amine-functionalized SBA-15 supports originated two heterogeneous catalysts PW@aptesSBA-15 and PW@tbaSBA-15. The best results were attained with the PW@aptesSBA-15 catalyst showing identical oxidative desulfurization performance as the homogeneous analogue. As advantage, this heterogeneous catalyst promotes the complete desulfurization of simulated diesel using a solvent-free system, i.e. without the need of acetonitrile use. On the other hand, the same desulfurization efficiency could be achieved using half the amount of oxidant (HO/S = 4). The oxidative desulfurization of the real diesel achieved a remarkable 83.4% of efficiency after just 2 h. The recycling capacity of PW@aptesSBA-15 catalyst was confirmed for eight consecutive cycles using the biphasic and the solvent-free systems. Its stability investigation demonstrates to be higher under the solvent-free system than the biphasic system, without practically any occurrence of PW leaching in the first case. On the other hand, the Venturello peroxocomplex [PO{W(O)} ], recognized as active intermediate in the homogeneous biphasic system, was not identified in the heterogeneous catalytic systems., This work was partly funded through the projects REQUIMTE-LAQV[FCT (Fundação para a Ciência e a Tecnologia) Ref. LAQV, REQUIMTE(POCI-01-0145-FEDER 007265, UID/QUI/50006/2013)] and CENIMAT, I3N (POCI-01-0145-FEDER-007688, UID/CTM/50025/2013) and UID/MULTI/00612/2013 (CQB),financed by national fundsthrough the FCT/MEC and when appropriate co-financed by the Fundo Europeu de Desenvolvimento Regional (FEDER) under the PT2020Partnership Agreement. The FCT and the European Union are ac-knowledged for the post-graduation grants SFRH/BD/95571/2013 (toSOR) and SFRH/BPD/73191/2010 (to CMG) co-funded by Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) and the European Social Fund through the program POPH of QREN. The authors alsoacknowledge the Portuguese Nuclear Magnetic Resonance Network (PTNMR).

Background Intestinal colonization by extended-spectrum cephalosporin-resistant Enterobacteriaceae (ESC-R-Ent) has been attributed to travel to high prevalence countries. However, the dynamics of the microbiota changes during ESC-R-Ent colonization and whether there is a particular bacterial composition which is associated with subsequent colonization is unknown. Methods Forty healthy volunteers living in Switzerland underwent screening before and after a trip to India, and also 3, 6 and 12 months after traveling. Culture-based ESC-R-Ent screening and microbiota analysis based on 16S rRNA amplicon sequencing were performed at all time points. Results Prevalence of ESC-R-Ent colonization before traveling was 10% (n = 4), whereas it increased to 76% (n = 31) after the trip. Based on bacterial diversity analyses of the gut microbiota, there were few but significant differences for colonized versus non-colonized individuals. However, an alternative, cluster based analysis revealed that individuals remained in the same cluster over time indicating that neither traveling nor ESC-R-Ent colonization significantly influences bacterial composition. Moreover, none of the found microbiota clusters were significantly associated with subsequent risk of ESC-R-Ent colonization. Conclusion Based on their microbiota patterns, every volunteer was at the same risk of ESC-R-Ent colonization while traveling to India. Therefore, other risk factors for ESC-R-Ent colonization are responsible for this phenomenon.

most colistin-resistant (Col-R) Klebsiella pneumoniae strains possess alterations of the two-component systems PhoP/Q and PmrA/B. These systems respond to environmental stimuli increasing the expression of the operon pmrHFIJKLM whose products are responsible for lipid A modifications leading to decreased affinity for polymyxins. This process is regulated by a negative feedback of the mgrB gene that encodes for a small protein repressing the PhoP/Q system. Thus, inactivation of mgrB leads to polymyxin resistance.

Globalization has increased the exposure of Supply Chains (SC) to higher uncertainties that call for adequate strategies, thus supporting the creation of SC Resilience. There is, however, no absolute strategy that decision makers can follow to guarantee such resilience and the knowledge on how to characterise SC resilience (SCR) is still an open issue. This work focuses on a strategic level of decision and analyses the relationship between SCR and SC complexity, aiming to conclude how SC flow complexity reflects SCR. The design and planning of a multi-product, multi-period SC are addressed through a Mixed Integer Linear Programming (MILP) model where demand uncertainty is considered. A set of disruptions is studied for different SC structures and as main conclusions, it can be stated that SC flow complexity leads to an increase in SC resilient performance and appears as a good indicator of SCR.

© 2014 Elsevier B.V. Porous clay heterostrucures (PCHs) are clay mineral based porous materials that have been mainly prepared by intercalation of structures with silica pore walls. In the present work the silica composition of the pore walls was modified by incorporating aluminum oxide, by a co-condensation methodology. Samples were characterized by nitrogen, water and toluene adsorption measurements. For the latter, heats of adsorption were measured using microcalorimetry. Characterization was also made by XRD, FTIR and chemical analysis by ICP and SEM-EDS. The materials were tested towards their selective adsorption properties, using chromatographic separation of toluene/. n-heptane and toluene/cyclohexane mixtures. The amounts of aluminum that were introduced in the PCHs by the co-condensation methodology without disrupting the porous structure were limited but, still, they were able to modify the selective adsorption properties of the samples. Above a certain value it produces disruption of the pore structure.

The activity and selectivity of bi-functional carbon-supported platinum catalysts for the hydroisomerization of n-alkanes have been studied. The influence of the properties of the carbon support on the performance of the catalysts were investigated by incorporating the metallic function on a series of carbons with varied porosity (microporous: GL-50 from Norit, and mesoporous: CMK-3) and surface chemistry (modified by wet oxidation). The characterization results achieved with H2 chemisorption and TEM showed differences in surface metal concentrations and metal–support interactions depending on the support composition. The highest metal dispersion was achieved after oxidation of the carbon matrix in concentrated nitric acid, suggesting that the presence of surface functional sites distributed in inner and outer surface favors a homogeneous metal distribution. On the other hand, the higher hydrogenating activity of the catalysts prepared with the mesoporous carbon pointed out that a fast molecular traffic inside the pores plays an important role in the catalysts performance. For n-decane hydroisomerization of long chain n-alkanes, higher activities were obtained for the catalysts with an optimized acidity and metal dispersion along with adequate porosity, pointing out the importance of the support properties in the performance of the catalysts., This work was financially supported by Fundação para a Ciência e Tecnologia (FCT) through Projects PTDC/CTM/65718/2006 and Pest-OE/QUI/UI0612/2011 (Strategic Project) and MINECO (CTM2011/23378). Authors wish to thank the collaboration of SALMON & Cia for supplying GL-50 carbon from NORIT

7 pages, 4 figures, 3 tables. -- PMID: 19006666 [PubMed]. -- Available online 8 November 2008., The removal of a widespread used drug (i.e., ibuprofen) from water was investigated using high valuable carbon adsorbents obtained from chemical and physical activation of a bioresource (cork) and a municipal waste (plastic). The waste-derived carbons outperformed the adsorption capacity of commercial carbonaceous adsorbents due to their adequate features for the removal of the targeted compound. Regarding the adsorption mechanism, the results obtained point out that ibuprofen retention is favored in activated carbons with basic surface properties. On the other hand, the textural features also play an important role; the presence of a transport pores network (i.e., mesopores) is crucial to ensure the accessibility to the inner porosity, and the microporosity must be large enough to accommodate the ibuprofen molecule. Specifically, adsorbents with a large fraction of ultramicropores (pore widths, This work was supported by FCT (Portugal) through the pluriannual programme of CQB. Ana S. Mestre thanks FCT for a PhD Grant (SFRH/BD/17942/2004). Conchi O. Ania thanks the Spanish MEC for a Ramon y Cajal research contract and the financial support of MICINN (Project CTM2008-01956/TECNO). The authors thank N.R. Neng and F.C.M. Portugal for technical assistance in HPLC measurements and Generis Farmacêutica SA (Portugal) for the ibuprofen supply. S.A. Bayer and S.L. Nanoquimia are kindly acknowledged for providing LS and Q carbons, respectively.

Pillared clays (PILCs), with Al, Zr and Al/Zr oxides, obtained from a natural montmorillonite from Benavila (Portugal), were investigated in terms of their structure (XRD), texture (N 2 and toluene adsorption), acidity (pyridine chemisorption) and catalytic performances on methylation of toluene. Zr content reflects on the d 001 values and on the acidity of PILCs, that present, besides Lewis sites, also Bronsted acid sites. All the solids showed activity to toluene alkylation revealing that, even the Bronsted acidic properties that proceed only from the clay sheets are enough to promote alkylation. A mixture of xylenes (XY) was obtained as the main reaction products, and the isomers distribution followed generally the order m ≥ o > p . Trimethylbenzenes (TMB) and ethyltoluenes (EtT) were also found, and on all the samples the selectivities were S xy >> S TMB > S EtT .

New molecular systems based on donor/acceptor groups connected by π-conjugated bridge, trans-[MoF(NNC7H6SO2)(Ph2PCH2CH2PPh2)2][BF4], have been synthesized. This complex with nonlinear optical (NLO) applications was immobilized by an adsorption process from liquid phase, in the interlayer of a pillared clay (PILC). The metal complex and the new materials were characterized by thermal analysis (DSC), chemical analysis, surface techniques (XPS), X-ray powder diffraction (XRD), nitrogen adsorption isotherms, spectroscopic methods (NMR, FT-IR and UV/Vis) and electrochemical measurements. The studies of the electrochemical and the spectroscopic properties of the complex show interactions between donor and acceptor groups across the conjugated bridge. The results obtained from the studies using different techniques of analysis confirm that the molybdenum complex was effectively immobilized in the host matrix and this process does not modify the morphology or structure of the PILC upon metal complex loading., Dr. Carmen Serra Rodrigues (C.A.C.T.I., Vigo University, Spain) is gratefully acknowledged for performing and analyzing the XPS measurements. We thank António Souza Azevedo for collecting the powder diffraction data. This work was supported by the Fundação para a Ciência e a Tecnologia (FCT, Portugal) through project POCTI/42931/QUI/2001., info:eu-repo/semantics/publishedVersion

This chapter describes textural and surface chemistry characterization of zeolites via adsorption phenomena. The studies in the literature on the characterization of the textural and surface chemistry of zeolites, zeotypes, and pillared materials via adsorption present different levels of agreement and contradiction. Adsorption is a broad term that involves the enrichment of one or more components in an interfacial layer. Zeolites are the most widely used catalysts in industry. In a large number of scientific publications, regarding their catalytic properties, adsorption studies are mainly used to measure surface areas or porous volumes, which either are treated as mere parameters given by automated apparatus, or are used in a somewhat uncritical way. Finally, in both situations a considerable amount of information, available from the same experimental work, can be lost.

Summary Low (γ) and high (γ') temperature Bi2O3.MoO3 phase have the same stoichiometry but markedly different structures. The catalytic activities of these phases for the 1-butene reactions in the presence of oxygen were studied with the aim of relating them to the structural differences. Low temperature phase is very active and selective. High temperature modification is much less active and leads to considerable degradation. TPD results allow to infer that the differences between the phases lead to formation of different active sites, involving oxygen vacancies on Mo6+ cations for the γ-phase and oxygen vacancies on Bi3+ cations for the γ'-phase. Furthermore an oxygen species not found on γ'-phase was detected on γ-phase.

IR spectroscopic studies have shown different surface complexes on three catalysts, i.e. Bi 2 O 3 ,.MoO 3 , γ-Al 2 O 3 , supported thallium oxide and γ-A1 2 O 3 supported metallic silver when exposed under continuous flow to a mixture of C 3 H 6 or C 2 H 4 and air. Spectra recorded after desorption in air were also different. These results can be related to the different catalytic behaviours observed in previous studies.