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International audience; Ultrasonic welding is a serious candidate in the development of methods to assemble papers and paperboards without using additional substances. However, the ultrasonic welding of papers remains a technological challenge considering the low weldability of lignocellulosic materials. This study aims to investigate on the ultrasonic welding process applied to papers in order to identify the processing conditions which favor the formation of strong welded joints. To reach such purpose, an experimental strategy was developed by combining the characterization of welded materials and the monitoring of process parameters. Experimentations were performed using a reference paper displaying a good weldability to specifically highlight the contribution of process parameters. Results indicate that the process is highly sensitive to vibration amplitude, power supplied by the high frequency generator, and sample thickness. Power seems to be a reliable indicator of the severity of the process. A strong decrease in the strength of the welded joints is observed when working with low thicknesses. It seems that the layers coated on top of papers are the main part of the material contributing in the development of adhesion at the welding joint. Overall, instrumenting the device has led to a better understanding of the ultrasonic welding of papers.

International audience; This paper focuses on the problem of the hierarchical multi‐label classification of research papers, which is the task of assigning the set of relevant labels for a paper from a hierarchy, using reduced amounts of labelled training data. Specifically, we study leveraging unlabelled data, which are usually plentiful and easy to collect, in addition to the few available labelled ones in a semi‐supervised learning framework for achieving better performance results. Thus, in this paper, we propose a semi‐supervised approach for the hierarchical multi‐label classification task of research papers based on the well‐known Co‐training algorithm, which exploit content and bibliographic coupling information as two distinct papers' views. In our approach, two hierarchical multi‐label classifiers, are learnt on different views of the labelled data, and iteratively select their most confident unlabelled samples, which are further added to the labelled set. The success of our suggested Co‐training‐based approach lies in two main components. The first is the use of two suggested selection criteria (i.e., Maximum Agreement and Labels Cardinality Consistency) that enforce selecting confident unlabelled samples. The second is the appliance of an oversampling method that rebalances the labels distribution of the initial labelled set, which reduces the reinforcement of the label imbalance issue during the Co‐training learning. The proposed approach is evaluated using a collection of scientific papers extracted from the ACM digital library. Performed experiments show the effectiveness of our approach with regards to several baseline methods.

International audience; The origin of Tibetan papermaking is poorly documented. Up to now, only the Tibetan paper fragments from Endere and Dunhuang sites have been scientifically studied outlining the basic knowledge about plant fiber uses and artwork manufacturing procedures. In order to deepen the knowledge on the unique ancient Tibetan papermaking, we report here the analysis of a set of paper fragments from the Samye Monastery in south Tibet, China. Multidisciplinary scientific investigations utilizing 14C radiocarbon dating, microscopic observation, scanning electron microscopy (SEM), pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), pyrolysis-comprehensive gas chromatography/mass spectrometry (Py-GCxGC/MS), and proteomic analysis have been applied to these ancient paper fragments. The results show that the fragments were dated to the 12th~13th century AD and made from fibers of the Thymelaeaceae family plant Stellera Chamaejasme L of which the fiber’s chemical profiles have been firstly studied. The presence of starch granules from Triticum spp wheat and proteins from bovine milk (more likely assigned to native yak), offers the first indication that a unique sizing technique using starch-milk sizing had been employed in early Tibetan papermaking, compared to using alum-animal glue sizing agent which is more popular in contemporary Central China. The combined use of organic material (unaltered starch grains) and inorganic material (calcium carbonate) as paper fillers is also firstly revealed in Tibetan papermaking. The application of Py-GC/MS, Py-GCxGC/MS and proteomic analysis revealed more detailed profiles of early Tibetan hand papermaking, indicating that these methods have great potential to explore the production technology of ancient handmade papers.

International audience; The durability of paper documents treated with aminoalkylalkoxysilane copolymer (co-AAAS) flexible networks, as deacidifying and strengthenening agents, was studied. To this end, a 1922 lignocellulos ic newsprint paper was treated with co-AAASs and characterized. Physico-chemical properties such as pH, chromatism, opacity and mechanical strength were measured shortly upon treatment and several years after. In order to better understand the role of the initial degradation state of the paper and the impact of its constituents other than cellulose (lignin, alum-rosin sizing) on the treatment efficiency, several laboratory papers were added as models. It was shown that alum-rosin sizing contributed to a decrease in pH of the most degraded treated paper over the monitoring time, whereas the strengthening effect was mostly affected by the presence of lignin. In particular, for most papers, after several years, the gain in folding endurance was the lowest in the lignin-rich ones. The breaking length of all the papers increased post-treatment and over time, independently of the paper constituents. This was attributed to the slowly progressing aminoalkylalkoxysilanes polycondensation, on the scale of years, as evidenced by Cross Polarisation-Mass Angle Spinning 29 Si solid-state Nuclear Magnetic Resonance.

In this work, we describe an eco-friendly and cost-efficient method for the production of highly dispersed few-layer graphene solution using karaya gum as bio-inspired exfoliating agent. The as-synthesized graphene aqueous solution can be easily applied on paper sheet through dip- or brush-coating thanks to the binding properties of the gum and to the functional groups on the paper surface with the graphene sheets. The as-synthesized composites display high mechanical strength and high electrical conductivity for numerous downstream applications. Electronic circuits can be designed on such graphene-paper composites either by controlling the graphene deposit or by post-laser etching with high lateral resolution. The laser beam can also be used to create local graphitization or partial etching of the conductive line in order to generate conductive areas with different resistance. The designed smart graphene paper was experimentally tested in different electronic applications, such as lightweight conductive circuit, as well as flexible keyboard which can be directly linked to a computer, thus opening up a new route for the development of daily life connected objects.

At the end of the 20th century, the future of the paper was not very optimistic due to the development of numerical technologies. Even if some paper grades have suffered, others like packaging boards, tissue papers and speciality papers have good economic trends. Furthermore, the environmental policies contribute to the development of natural fibre based materials and also to reuse a maximum of materials. Another important point to take into account is the climate warming, the fossil resources depletion and the trade globalization. All of that leads to new potential resources in order to produce greener paper and board. This chapter highlights the origin of natural fibres which could be used in the pulp and paper business, describes briefly the pulping and papermaking processes including some aspects about the specificity of the use of annual plants and to presents some new challenges for papermakers.

Generated in the pulp and paper production process, cellulosic pulp fines are fibrous cellulosic materials capable of passing a 200 mesh screen. Processed pulp fines remain in the pulp and affect pulp and paper sheet properties. Their specific morphology promotes interactions with fibers and alters sheet properties. Nevertheless, the 3D distribution of fines in paper sheets has not been revealed so far. Localizing fines within a matrix of fibers is challenging since both elements have the same chemical composition and fines have small dimensions. It is required to increase the contrast of pulp fines, while avoiding any alteration of initial fines morphology. In this study, fines were first separated and labeled with Rhodamine B isothiocyanate, a fluorescent dye. Labeled fines were blended with pulp at different concentrations and paper sheets were produced from each mixture. Prior to imaging, pulps and handsheets were characterized by standard pulp and paper tests and compared with references, showing no significant differences between sheets containing labeled and untreated fines. Thus, mechanical and physical tests indicated that no, or only minor alteration of fines properties by the labeling process occurred. We then applied two imaging techniques to detect the labeled pulp fines in the paper network, namely confocal laser scanning microscopy and multiphoton microscopy, visualizing the 3D distribution of fluorescent fines within the fiber network. The results obtained also allowed a differentiation between morphologically different fines showing fiber fragments more attached to single fibers whereas more fibrillar fines concentrate in fiber–fiber joints, thereby strengthening bonding.

International audience; The hemp plant Cannabis sativa Linn, referring to industrial hemp, is a high-yielding annual industrial crop grown providing fibers from hemp stalk and oil from hemp seeds. Although hemp is a niche crop, hemp production is currently undergoing a renaissance. More than 30 countries grow hemp, with China being the largest hemp producing and exporting country. Europe and Canada are also important actors in the global hemp market. Traditionally, hemp as a fiber plant has been used for the production of apparels, fabrics, papers, cordages and building materials. The hurds, as waste by-product of fiber production, were used for bedding of animals, the seeds for human nutrition, e.g., as flour, and the oil for a wide range of purposes, from cooking to cosmetics. Hemp has also been an important crop throughout human history for medicine. Other more recent applications include materials for insulation and furniture, automotive composites for interior applications and motor vehicle parts, bioplastics, jewelry and fashion sectors, animal feed, animal bedding, and energy and fuel production. Foods containing hemp seed and oil are currently marketed worldwide for both animal and human nutrition. They also find applications in beverages and in neutraceutical products. Hemp oil is also used for cosmetics and personal care items, paints, printing inks, detergents and solvents. It is estimated that the global market for hemp consists of more than 25,000 products. Currently, the construction and insulation sector, paper and textile industries, and food and nutrition domains are the main markets while the cosmetics and automotive sector are growing markets. Innovative applications, e.g., in the medical and therapeutic domains, cosmeceuticals, phytoremediation, acoustic domain, wastewater treatment, biofuels, biopesticides and biotechnology, open new challenges. Hemp is also the object of numerous fundamental studies. This review presents and discusses the traditional and new uses of industrial hemp.

This work develops a multi-objective linear programming model for a multi-echelon, multi-product, multi-period supply chain planning. This model considers all dimensions of sustainable development paradigm simultaneously and expands six objective functions for making the model realistic. To solve this model and large-scale sustainable supply chain management, an improved version of the augmented e-constraint method (AUGMECON2) is used. Computational results illustrate the proposed model admitted various progresses in all the three pillars of sustainable development; namely remarkable progress, mildly progress and irregular one, respectively. In addition, important managerial insights are provided. Trade-off interactions between multi-objectives are perceived by the obtained Pareto solutions that represents the cost of being sustainable from the point of optimizing the social factors and environmental impacts. An application to the paper industry is presented and discussed.

Swarms of autonomous aircraft systems (SAAS) are used to accomplish missions that deal with sensitive and critical data. As such, these systems are subject to attacks among which clone attacks. Several clone attacks detection approaches either in stationary or mobile wireless sensor networks have been proposed. Unfortunately, the existing approaches are not suitable for swarms of autonomous aircraft systems because either they do not guarantee a fast enough detection (while most SAAS missions are real time missions, e.g. surveillance), or they depend on strong assumptions that are hard to achieve in practice (e.g. absence of nodes collusion, impossibility for an attacker to track a genuine node). In this paper, we present a novel clone attack detection approach specific to SAAS that solves several unaddressed issues and that makes it possible to improve the security and the privacy of the assets of the SAAS.

Cellulose is an attractive reagent for the elaboration of C-containing materials, but here, we also considered it as an O-provider for preparing macro, micro and nano-fibrous Nb2O5/C composites by a new mineralization with Nb2Cl10 in anhydrous conditions. Our study highlights differences of reactivity between filter paper, microfibrillated or bacterial cellulose in connection with the crystallinity and the accessibility of the hydroxyl groups. The Nb2O5/C ratio was found to be adjustable (55?75% of Nb oxide) depending on the cellulosic precursor. Our composites were tested as electrodes that could be used as negative electrode in hybrid lithium-capacitor. Electrochemical characterizations of Nb2O5/C composites are reported and it was demonstrated that characteristics of the starting cellulosic reagents that influence physico-chemical properties of composites thus impact electrodes performances. Very interestingly, for 1C charging/discharging rates, capacities as good as thus of literature (150 mAh g−1) were obtained using our new sustainable synthesis protocol. Fil: Henry, Aurélien. Université Montpellier II; Francia Fil: Le Vot, Steven. Université Montpellier II; Francia Fil: Alauzun, Johan G.. Université Montpellier II; Francia Fil: Hesemann, Peter. Université Montpellier II; Francia Fil: Foresti, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnología en Polímeros y Nanotecnología. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnología en Polímeros y Nanotecnología; Argentina Fil: Cerruti, Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnología en Polímeros y Nanotecnología. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnología en Polímeros y Nanotecnología; Argentina Fil: Heux, Laurent. Université Montpellier II; Francia Fil: Fontaine, Olivier. Université Montpellier II; Francia Fil: Boury, Bruno. Université Montpellier II; Francia

International audience

International audience; Complex cellulosic samples are often difficult to analyse with size-exclusion chromatography. The strong molecular associations of hemicelluloses and lignin with cellulose produce multimodal molar mass distributions (MMD) that are difficult to interpret. More reliable ways of calculating the molar masses of cellulose are thus necessary. This is particularly relevant when studying the kinetics of paper degradation, as the number average molar mass is the most precise indicator. In this study various data handling methods based on the deconvolution of bimodal and multimodal MMDs of complex cellulosic samples after SEC-MALS-DRI analysis are examined in order to propose more accurate paper degradation rates. Two deconvolution methods, which do or do not rely on polymer calibration curves were developed and were applied to several kraft and groundwood pulp papers unaged and hygrothermally aged. The deconvolution methods are discussed and evaluated in light of calculated cellulose activation energies, degradation rates and paper usable lifetime predictions.

In order to make 2nd-generation biofuels more competitive, high solid-matter content has to be reached. To progress towards this target, the mechanism for destructuring lignocellulose fibres in semidilute conditions has to be well understood, as this configuration shows the basic mechanism which limits transfers and efficiency. This study aims to delve deeply into the biophysical and transfer limitations occurring during enzymatic hydrolysis. A specific experimental set-up associating in-situ and ex-situ physical (rheometry, chord length analysis) and biochemical analysis was used to expand the knowledge of hydrolysis of extruded softwood paper pulp over 24 h under different substrate concentrations (1%–3%) and enzyme doses (Accellerase 1500, 5 and 25 FPU/g cellulose). Non-Newtonian behaviour associated with pronounced yield stress stand as the major factors limiting process efficiency. A critical time was deduced from viscosity evolution, and the existence of a unique, dimensionless viscosity-time curve was established, suggesting similar mechanisms for fibre degradation. In addition, chord length distribution allowed for the description of population evolution and was discussed in the light of in-situ viscosity and hydrolysis yield. Physical (viscosity, particle size) and biochemical (substrate) kinetics were modelled (second-order) and coefficients identified. A chronology of the encountered phenomenological limitations demonstrates the necessity of optimising bioprocesses by considering physical parameters. A reference feed rate is proposed in order to reach high solid loading under fed-batch strategy.

cited By 0; In this work, we design new plasmonic paper-based nanoplatforms with interesting capabilities in terms of sensitivity, efficiency, and reproducibility for promoting multimodal biodetection via Localized Surface Plasmon Resonance (LSPR), Surface Enhanced Raman Spectroscopy (SERS), and Metal Enhanced Fluorescence (MEF). To succeed, we exploit the unique optical properties of gold nanobipyramids (AuBPs) deposited onto the cellulose fibers via plasmonic calligraphy using a commercial pen. The first step of the biosensing protocol was to precisely graft the previously chemically-formed p-aminothiophenol@Biotin system, as active recognition element for target streptavidin detection, onto the plasmonic nanoplatform. The specific capture of the target protein was successfully demonstrated using three complementary sensing techniques. As a result, while the LSPR based sensing capabilities of the nanoplatform were proved by successive 13-18 nm red shifts of the longitudinal LSPR associated with the change of the surface RI after each step. By employing the ultrasensitive SERS technique, we were able to indirectly confirm the molecular identification of the biotin-streptavidin interaction due to the protein fingerprint bands assigned to amide I, amide III, and Trp vibrations. Additionally, the formed biotin-streptavidin complex acted as a spacer to ensure an optimal distance between the AuBP surface and the Alexa 680 fluorophore for achieving a 2-fold fluorescence emission enhancement of streptavidin@Alexa 680 on the biotinylated nanoplatform compared to the same complex on bare paper (near the plasmonic lines), implementing thus a novel MEF sensing nanoplatform. Finally, by integrating multiple LSPR, SERS, and MEF nanosensors with multiplex capability into a single flexible and portable plasmonic nanoplatform, we could overcome important limits in the field of portable point-of-care diagnostics. © 2019 Campu, Susu, Orzan, Maniu, Craciun, Vulpoi, Roiban, Focsan and Astilean.

session: Antenna and Propagation; International audience; The design of antennas on cellulosic flexible materials such as paper can be very challenging because of the limited thickness and the high losses in the Radio Frequency (RF) domain. In this paper, a novel patch antenna with an origami structure is proposed to address the null radiation efficiency obtained with the conventional paper-based structure. As the electromagnetic waves mostly travel in the air, ideal conditions such as no loss and a low dielectric constant allow for the asymptotic value of directivity of microstrip antennas to be reached with a 63 % experimental radiation efficiency. This flexible antenna can be used for RF energy harvesting or sensing applications due to the sensitivity of paper on atmospheric conditions.

International audience; This paper addresses the problem of building recommender systems for scientific papers based on the linguistic and contextual analysis of citation contexts. We explain the importance of taking into consideration citation contexts and the different methodologies that exist as well as the ways that citations impact recommender systems. We also discuss the limits of using citation contexts to generate recommendations.

Various parameters that may affect the efficiency of tri- and di-functional aminoalkylalkoxysilanes (AAAS) copolymer treatments to deacidify and mechanically strengthen aged complex papers (lignocellulosic pulp, additives) were studied. Three model papers were first hydrothermally aged (90 °C—50% RH) in order to achieve physicochemical characteristics similar to those of a naturally aged newsprint, and were then treated with AAAS copolymers. The chemical composition of the treatments varied from 50 to 5 wt% of tri-functional monomer APTES, the latter acting as cross-linker in the copolymer network. The respective ratio of tri- and di-functional monomers in the mixture was shown to greatly influence the mechanical properties of the treated papers in the case of APTES/DIAMINO but less so in the case of APTES/AMDES. If APTES/DIAMINO (50/50 wt%) did not strengthen the degraded papers, a higher proportion of DIAMINO (95 wt%) and lower proportion of APTES (5 wt%) led to improving the tensile strength and, more importantly for the function properties of paper, significantly enhancing the folding endurance. The treatment efficiency decreased at higher state of deterioration of the papers and in the presence of alum–rosin sizing. Lastly, the treatments developed for the artificially aged model papers were applied to the degraded newsprint paper specimen and successfully enhanced its mechanical properties.

International audience; Advanced internet and multimedia set-top boxes are today massively based on 4*4 MIMO systems, with multi-sub-bands standards (Wifi bands, LTE, Bluetooth,…). Multiple antennas spatially distributed on the plastic casing become therefore a great challenge for cost and performances motivations, thus promoting flexible technology and substrate, for assembling subsystems , under compactness considerations, as well as electrical performances improvement. In this paper, we discuss about the characterisation of Multi-band antennas designed on an ultra-low cost material (a cellulosic substrate, i.e. a paper) with design challenges in terms of radiation efficiency maximization and wideband properties under compactness constraints. Simulation and measurements are proposed to validate the designs.

Fibrous cellulosic materials have been used as templates for material synthesis or organization via thermal degradation of the cellulose. Most of these methods, however, fail to exploit fiber organization, in part due to loss of structure with processing. Herein, we demonstrate that chemi- and physi-sorbed modifiers of cellulose alters the thermal degradation mechanism allowing for controlled deposition of oxide and carbon (incomplete combustion) along the original paper fiber network. We demonstrate that the degradation of the cellulose fibers depends on the amount of physisorbed material due, in part, to effect on the propagation of the ignition event. From the distribution of the residual elements and shape of the deposits, we can infer that the thermal degradation process depends on the nature, and concentration, of filler(s) or occluded.

International audience; A cellulose paper sheet, chemically modified with azide functions, is described to be a versatile molecular platform for copper-catalyzed 1,3-dipolar cycloaddition with terminal alkynes. This 3-step methodology was carefully optimized at each stage of the process with the support of experimental and physical evidences. Our approach allows the surface coverage of structurally diverse molecular architectures through a covalent grafting with non-hydrolysable chemical linkers. This robust linkage is highlighted with the surface hydrophobization of cellulose paper through the click ligation of cholesterol units as renewable and inexpensive hydrophobic agents. The resulting water-resistant and water-repellent paper-based material shows powerful oleophilicity properties and displays a high contact angle of 139.6°.

International audience; We study the mechanical response, and tearing features of crêpe paper, a two-dimensional, very anisotropic material, with one direction much less stiff than the other one. Depending on how the soft direction has been pre-stretched or not, the apparent Young modulus of the material can be varied over a broad range, while its fracture energy remains unaltered. The classical tearing concertina problem shows that a macroscopic measurement (the shape of the teared region) provides a direct access to the fracture properties of the material (effective Young's modulus, and fracture energy). The overall discussion is conducted in the frame of Griffith's theory of fracture.

International audience; We report a novel fully printed RFID based sensor fabricated on paper substrate. The sensitive material is wheat gluten which is a biopolymer having electrical parameters correlated with relative humidity (RH). The sensor is validated with simulation and measurement results varying climatic conditions.

International audience; To reduce pollution emissions and achieve a cleaner production in paper industry, it is essential to understand the inner links between concentrations of gaseous pollutants, types of final products and production techniques. In this study, the concentrations of four potential gaseous pollutants, total volatile organic compounds (TVOC), formaldehyde (HCHO), hydrogen sulfide (H 2 S), and hydrocarbon compounds (C x H y), in the ambient air on thirty sampling points of five pulp and paper mills were detected and analyzed. The results were summarized with respect to the following aspects: (1) Levels of four gaseous pollutants on all the sampling points in five mills. It was obvious that the situation of gaseous pollution from pulp mill was much more serious than those from paper mills. (2) Gaseous pollutant distinctions due to different production processes. The levels of gaseous pollutants from five mills were greatly influenced by the utilized raw materials and the applied paper chemical agents (flavor, coating materials and additives) in mills. (3) Gaseous pollution comparisons at common points. At the two common points in five mills, i.e. the wet end of paper machine and the wastewater treatment process, TVOC and HCHO, C x H y and H 2 S were the main gaseous pollutants, respectively. In addition, some feasible measures to realize a cleaner production in pulping and papermaking process were also put forward in the article.

International audience; The aim of the research was to evaluate the influence of certain components of paper such as lignin and papermaking additives (fillers and sizing) on the efficiency of a recently proposed treatment for simultaneous deacidification and mechanical strengthening with polyaminosiloxane copolymer networks. Mixed mechanical and chemical pulp papers containing various additives were treated with aminoalkylalkoxysilanes (AAAS) by immersion or by spray. Upon treatment, the deposited alkaline reserve varied from 0.34 to 1.14 mol kg −1 . For all the papers, copolymers formed from binary mixtures of a di- and a tri-functional AAAS provided the best improvement in the mechanical properties, i.e. in the tensile strength and the folding endurance, indicating an increase in the interfiber bonding energy and in the paper flexibility and plasticity, respectively. It was found that fillers had no influence while sizing hampered the efficiency of the treatment. The presence of mechanical pulp was shown to have a significant impact on the effect of the treatments as well by increasing the tensile resistance more than the folding endurance, indicating an increase in the paper rigidity. This observation was attributed to the response of lignin to the treatment.

Fine prediction of the elastic properties of paper materials can now be obtained using sophisticated fibre scale numerical approaches. However, there is still a need, in particular for low-density papers, for simple and compact analytical models that enable the elastic properties of these papers to be estimated from the knowledge of various structural information about their fibres and their fibrous networks. For that purpose, we pursued the analysis carried out in Marulier et al. (Cellulose 22:1517–1539, 2015. https://doi.org/10.1007/s10570-015-0610-6 ) with low-density papers that were fabricated with planar random and orientated fibrous microstructures and different fibre contents. The fibrous microstructures of these papers were imaged using X-ray synchrotron microtomography. The corresponding 3D images revealed highly connected fibrous networks with small fibre bond areas. Furthermore, the evolutions of their Young’s moduli were non-linear and evolved as power-laws with the fibre content. Current analytical models of the literature do not capture these trends. In light of these experimental data, we developed a fibre network model for the in-plane elasticity of papers in which the main deformation mechanisms of the micromechanical model is the shear of the numerous fibre bonds and their vicinity, whereas the fibre parts far from these zones were considered as rigid bodies. The stiffness tensor of papers was then estimated both numerically using a discrete element code and analytically using additional assumptions. Both approaches nicely fit the experimental trends by adjusting a unique unknown micromechanical parameter, which is the shear stiffness of bonding zones. The estimate of this parameter is relevant in light of several recently reported experimental results.

International audience; We clarify some analytical expressions existing in the literature, • Within the correct formulae we conclude that there is no need for an ad hoc improvement on the opposite to the title paper, • We highlight the symmetry properties of the function to be integrated in order to agree with the usual assumptions made to derive the Kramers-Kronig relations, • The analytical formula we provide may be used to increase the accuracy of the "Poor Man's Kramers-Kronig analysis" method and the "Kramers-Kronig constrained variational analysis" method.

International audience; Among the programming models for parallel and distributed computing, one can identify two important families. The programming models adapted to data-parallelism, where a set of coordinated processes perform a computation by splitting the input data; and coordination languages able to express complex coordination patterns and rich interactions between processing entities. This article takes two successful programming models belonging to the two categories and puts them together into an effective programming model. More precisely, we investigate the use of active objects to coordinate BSP processes. We choose two paradigms that both enforce the absence of data-races, one of the major sources of error in parallel programming. This article explains why we believe such a model is interesting and provides a formal semantics integrating the notions of the two programming paradigms in a coherent and effective manner.

International audience; An analytical approach based on the multivariate analysis of on-line pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) data is proposed for the identification of traditional East Asian handmade papers from different fiber material origins. This approach utilized several biomarkers detected during Py-GC/MS analysis of the paper samples. At first, the total ion chromatogram (TIC) was taken as the response and then the extracted ion chromatograms (EICs) were considered to improve the discrimination of papers. The influence of different data pretreatment (raw responses vs normalized values) including different weighting of the variables (weighting as 1 vs weight as 1/STD, where STD stands for standard deviation) for principal component analysis was also investigated. The results showed that compared to the commonly used microscopy techniques, the Py-GC/MS technique proved to be able to discriminate against handmade paper materials that have similar microscopic morphologies such as Morus species vs. Broussonetia species. The data pretreatment influenced the PCA modeling: the analysis based on normalized values showed more interpretable PCA group features for Moraceae species. PCA without weighting resulted unsurprisingly in discrimination through the presence of high intensity response biomarkers, while when applying weight as 1/STD, PCA loading plot was shown to provide a group of compounds, most of them being present at low levels, to be discriminating. Additionally, the characteristic EICs can provide data matrix for statistical analysis avoiding the interference from co-eluting compound and background compared to the data matrix obtained from the TIC. As a result, a quick Py-GC/MS based handmade paper identification procedure using PCA modeling of characteristic EICs was for the first time proposed in the identification of traditional East Asian handmade papers. This procedure could be very beneficial in cultural heritage applications.

In this paper, we report the first successful implementation of a complete paper-based water management system (WMS) that collects the excess water at the cathode of a microfabricated packageless fuel cell (PLFC) and redistribute it to its anode and to an evaporation surface that simulate a hydride-based hydrogen generator. Five configurations of WMS were tested on a 1 cm2 air-breathing PLFC and show that with the best configuration, the power output of the cell can be improved by 90% for at least 24h. We experimentally demonstrate that not only cathode flooding issues must be address to obtain an efficient WMS but also that anode drying plays a major role in poor performance of small air-breathing fuel cells. Finally, with the optimal configuration of WMS, the PLFC in air-breathing mode shows similar performances as with humidity controlled air forced-flow.

International audience; The diagnosis of infectious diseases is entering a new and interesting phase. Technologies based on paper microfluidics, coupled to developments in isothermal amplification of Nucleic Acids (NAs) raise opportunities for bringing the methods of molecular biology in the field, in a low setting environment. A lot of work has been performed in the domain over the last few years and the landscape of contributions is rich and diverse. Most often, the level of sample preparation differs, along with the sample nature, the amplification and detection methods, and the design of the device, among other features. In this review, we attempt to offer a structured description of the state of the art. The domain is not mature and there exist bottlenecks that hamper the realization of Nucleic Acid Amplification Tests (NAATs) complying with the constraints of the field in low and middle income countries. In this domain however, the pace of progress is impressively fast. This review is written for a broad Lab on a Chip audience.

International audience; Cellulose paper degradation products forming in the “tideline” area at the wet-dry interface of pure cellulose paper were analyzed using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) and high-resolution electrospray ionization-mass spectrometry (ESI-MS, LTQ Orbitrap) techniques. Different extraction protocols were employed in order to solubilize the products of oxidative cellulose decomposition, i.e., a direct solvent extraction or a more laborious chromophore release and identification (CRI) technique aiming to reveal products responsible for paper discoloration in the tideline area. Several groups of low molecular weight compounds were identified, suggesting a complex pathway of cellulose decomposition in the tidelines formed at the cellulose-water-oxygen interface. Our findings, namely the appearance of a wide range of linear saturated carboxylic acids (from formic to nonanoic), support the oxidative autocatalytic mechanism of decomposition. In addition, the identification of several furanic compounds (which can be, in part, responsible for paper discoloration) plus anhydro carbohydrate derivatives sheds more light on the pathways of cellulose decomposition. Most notably, the mechanisms of tideline formation in the presence of molecular oxygen appear surprisingly similar to pathways of pyrolytic cellulose degradation. More complex chromophore compounds were not detected in this study, thereby revealing a difference between this short-term tideline experiment and longer-term cellulose aging.

Fault diagnosis of sequential batch reactor (SBR), a widely applied wastewater treatment technology in papermaking industry with huge discharge, has been a significant challenge due to the inherent multi-period characteristics of the process. In this paper, based on the conventional multi-way principal component analysis (MPCA) method (Scenario 0), two sub-period division strategies based on the processing phases of SBR process (Scenario 1) and the similarities of the loading matrices between the adjacent time slices (Scenario 2) are proposed for the detection of faults. Combined with Scenario 0, using the field data of blower current, level of SBR reactor, dissolved oxygen of wastewater and the blower valve opening in the SBR process of paper mill, two different fault diagnosis models with Scenarios 1 and 2 are developed and evaluated, respectively. The study results revealed that, both the calculated statistics of T2 and sum of prediction errors (SPE) of the fault diagnosis models with Scenarios 1 and 2 could detect the faults and identify the fault locations and sources. Compared to Scenario 0 which neglects the correlations between the different stages of SBR process, the fault diagnosis model by Scenario 2 demonstrated a superiority ability in fault identification in terms of the fault’s time onset and fault’s sources with adequate accuracy. The results enable the feasible and reliable implementation of the developed sub-MPCA diagnosis model with Scenario 2 in the actual SBR plants.

The use of cyclopropenone derivatives as latent photo-released strained cyclic alkynes is reported for the covalent printing of complex patterns on cellulose paper. Two different approaches using either a UV LED or a laser as light irradiation source are discussed. While the high intensity of the laser damages the grafted molecular layer, the use of a simple UV LED allows the printing in only 8 min at room temperature with a good resolution at the micrometer scale with negligible diffusion. The validity of this strategy is demonstrated through the sequential printing of a QR code and a logo on the same paper sheet.

International audience; This paper presents the design, implementation, and prototype of a low-cost Braille embossing mechanism. The proposal is a printer head integrating three hammers that, upon actuation, stamp readable dots on the paper. Inspired in the rotary cam-follower mechanism, the hammers are actuated by a single servomotor which rotation determines which hammer strikes the paper. Braille characters can be quickly embossed using the proposed printer head. Affordable and efficient Braille embossers for home use can be envisaged using this new action approach.

Part 3: Recommendation System; International audience; Vector representations learning (also known as embeddings) for users (items) are at the core of modern recommendation systems. Existing works usually map users and items to low-dimensional space to predict user preferences for items and describe pre-existing features (such as ID) of users (or items) to obtain the embedding of the user (or item). However, we argue that such methods neglect the dual role of users, side information of users and items (e.g., dual citation relationship of authors, authoritativeness of authors and papers) when recommendation is performed for scientific paper. As such, the resulting representations may be insufficient to predict optimal author citations.In this paper, we contribute a new model named scientific paper recommendation using Author’s Dual Role Citation Relationship (ADRCR) to capture authors’ citation relationship. Our model incorporates the reference relation between author and author, the citation relationship between author and paper, and the authoritativeness of authors and papers into a unified framework. In particular, our model predicts author citation relationship in each specific class. Experiments on the DBLP dataset demonstrate that ADRCR outperforms state-of-the-art recommendation methods. Further analysis shows that modeling the author’s dual role is particularly helpful for providing recommendation for sparse users that have very few interactions.

International audience; Whenever a bug or vulnerability is detected in the Linux kernel, the kernel developers will endeavour to fix it by introducing a patch into the mainline version of the Linux kernel source tree. However, many users run older "stable" versions of Linux, meaning that the patch should also be "backported" to one or more of these older kernel versions. This process is error-prone and there is usually a long delay in publishing the backported patch. Based on an empirical study, we show that around 8% of all commits submitted to Linux mainline are backported to older versions, but often more than one month elapses before the backport is available. Hence, we propose a patch backporting technique that can automatically transfer patches from the mainline version of Linux into older stable versions. Our approach first synthesizes a partial transformation rule based on a Linux mainline patch. This rule can then be generalized by analysing the alignment between the mainline and target versions. The generalized rule is then applied to the target version to produce a backported patch. We have implemented our transformation technique in a tool called FixMorph and evaluated it on 350 Linux mainline patches. FixMorph correctly backports 75.1% of them. Compared to existing techniques, FixMorph improves both the precision and recall in backporting patches. Apart from automation of software maintenance tasks, patch backporting helps in reducing the exposure to known security vulnerabilities in stable versions of the Linux kernel.

International audience; Inkjet-printed PEDOT:PSS electrodes are shown to record cutaneous electrophysiological signals such as electrocardiograms via a simple finger-to-electrode contact. The recordings are of high quality and show no deterioration over a 3 month period, paving the way for the development of the next generation of low-cost, convenient-to-use healthcare monitoring devices.

Proof assistants are getting more widespread use in research and industry to provide certified and independently checkable guarantees about theories, designs, systems and implementations. However, proof assistant implementations themselves are seldom verified, although they take a major share of the trusted code base in any such certification effort. In this area, proof assistants based on Higher-Order Logic enjoy stronger guarantees, as self-certified implementations have been available for some years. One cause of this difference is the inherent complexity of dependent type theories together with their extensions with inductive types, universe polymorphism and complex sort systems, and the gap between theory on paper and practical implementations in efficient programming languages. MetaCoq is a collaborative project that aims to tackle these difficulties to provide the first fully-certified realistic implementation of a type checker for the full calculus underlying the Coq proof assistant. To achieve this, we refined the sometimes blurry, if not incorrect, specification and implementation of the system. We show how theoretical tools from this community such as bidirectional type-checking, Tait-Martin-L\"of/Takahashi's confluence proof technique and monadic and dependently-typed programming can help construct the following artefacts: a specification of Coq's syntax and type theory, the Polymorphic Cumulative Calculus of (Co)-Inductive Constructions (PCUIC); a monad for the manipulation of raw syntax and interaction with the Coq system; a verification of PCUIC's metatheory, whose main results are the confluence of reduction, type preservation and principality of typing; a realistic, correct and complete type-checker for PCUIC; a sound type and proof erasure procedure from PCUIC to untyped lambda-calculus, i.e., the core of the extraction mechanism of Coq., Comment: In Proceedings LFMTP 2021, arXiv:2107.07376

International audience; Hydrophilic porous substrates, in particular paper, are now widely used for the fabrication of microfluidic devices. These materials are very attractive because of their low-cost and their ability to generate capillary flow. Such materials avoid the need of external pressure sources or syringe pumps. However, capillary flows wicking a hydrophilic fiber matrix experience non-specific adsorption and depend on environmental conditions such as humidity. In this article a novel fabrication method is proposed to create low-cost embossed-paper microfluidic devices allowing for spontaneous capillary flow. Thus, embossing is used to design hollow microfluidic channels and chambers on a waterproof and hydrophilic paper surface. Because the hollow-channels obtained are fiber-free, the issues of imbibition are avoided. Besides, the paper surface being hydrophilic, the capillary flow in the embossed device is spontaneous. Thus, such microfluidic devices provide an efficient support to perform diagnostics in resource-poor settings. In this work, it is shown that a colorimetric glucose detection can be achieved using embossed-paper channels. The detection is achieved in twelve minutes, either by naked eyes or by analyzing pictures taking with a smartphone camera for quantification.

International audience; IntroductionIn January 2015, Rouen University Hospital’s information system experienced serious issues. It was necessary to rapidly switch from the computerized provider order entry (CPOE) system towards a paper-based order entry (PBOE) system. This was an opportunity to evaluate prescriber opinion on the two provider order entry (POE) systems.MethodsAll residents were asked to fill an augmented version of the POE satisfaction and usage survey for both POE systems. The results were compared to identify the strengths and weaknesses of each system.ResultsFifty-one respondents had used the CPOE system and the PBOE system. Overall, satisfaction was higher with PBOE than CPOE (odds ratio (OR) = 3.74; p < 0.001). Usability (OR = 4.00; p < 0.001), reliability (OR = 8.54; p < 0.001), time consumption (OR = 0.50; p < 0.05 – survey statement was formulated negatively), and communication with nurses (OR = 14.27; p < 0.0001) reached statistically better agreement. The more experience with CPOE the more residents were disillusioned with the reliability (OR = 6.55; p < 0.01), the usability (OR = 5.68; p < 0.01) and the patient safety (OR = 0.27; p < 0.05 – survey statement was formulated negatively) of CPOE. Although safety issues were reported for both systems, the causes were different; PBOE imposed frequent rewriting of the order while CPOE lack of usability might be unsafe. Another important issue with both POE systems was time consumption.ConclusionResidents did not report any increase in safety issues with the rapid switch from CPOE to PBOE. They even seemed more satisfied with the rollback to paper, which remains a possible degraded mode in case of health information technology collapse.

A chemically modified cellulose filter paper with ethylenediaminetetraacetic acid (EDTA) is described as a device for metal remediation. This new material was prepared by esterification of the paper with EDTA dianhydride. The high hydrophilicity of cellulose paper associated with the strong chelating properties of the EDTA moieties for metals allow the treatment of water samples containing various metal cations, including Ag(I), Pb(II), Cd(II), Ni(II), Zn(II), Sn(II), and Cu(II), with 90–95% removal efficiency. The mechanism of adsorption was deeply studied with the support of kinetic experiments and adsorption isotherms. As a practical feature, one can note that the cellulose–EDTA material works at a wide range of pH values and can be used either as a solid adsorbent or a membrane for continuous wastewater treatment.

International audience; The task of tagging papers with semantic metadata in order to analyze their relatedness represents a good foundation for a paper recommender system. The analysis from this paper extends from previous research in order to create a graph of papers from a specific domain with the purpose of determining each article's importance within the considered corpus of papers. Moreover, as non-latent representations are powerful when used in conjunction with latent ones, our system retrieves semantically close words, not present in the paper, in order to improve the retrieval of papers. Our previous analyses used the semantic representation of papers in different semantic models with the purpose of creating visual graphs based on the semantic relatedness links between the abstracts. The current analysis takes a step forward by proposing a model that can suggest which papers are of the highest relevance, share similar concepts, and are semantically related with the initial query. Our study is performed using paper abstracts in the field of information technology extracted from the Web of Science citation index. The research includes a use case and its corresponding results by using interactive and exploratory network graph representations.

International audience; We tested the performance of pyrolysis-comprehensive two-dimensional gas chromatography/massspectrometry in the course of our cultural heritage studies, and compared its potentialities for the char-acterization of traditional East Asian handmade papers with those previously obtained by pyrolysis-gaschromatography/mass spectrometry. The evaluation of the two methods was conducted in consider-ing the number of detected peaks, the compounds separation, the sensitivity, and the identificationof marker compounds. The results showed that the number of plant markers (triterpenes and phytos-terols) detected in a Japanese kozo reference paper was improved in the pyrolysis fingerprint. With again in sensitivity in the order of six, the case study of a museum sample confirmed that pyrolysis-comprehensive two-dimensional gas chromatography/mass spectrometry is more efficient for a reliableidentification of museum collections samples and/or archaeological samples where tiny quantities ofmaterials are the rule. The present study has been successful in refining a micro-destructive methodbased on analytical pyrolysis for the characterization of traditional East Asian handmade papers usingpyrolysis-comprehensive two-dimensional gas chromatography/mass spectrometry.

International audience

International audience; Porous 3-D current collectors have been shown to be the primary choice in replacing classical 2D aluminum foil in applicable developments, especially those using carbon-based current collectors. In this study, we investigated the impact of using a non-woven carbon (NWC) based current collector for sulfur electrodes, in terms of performance and practical use in a commercial battery, keeping in mind the simplicity of electrode preparation method. The benefits of using NWC as a 3D current collector include high sulfur utilization for even highly loaded electrodes, lower polarization, and the provision of an efficient electrolyte reservoir. High discharge capacities up to ∼1200 mAh g−1 can be obtained at moderate C-rates, with relatively good capacity retention (

A review of the most important findings for jets impingement on rotating target is presented, the focus is on the heat transfer and flow dynamics in these jets. These jet configurations are encountered in many industrial applications. A significant number of research studies dealing with computational and experimental studies are reviewed. Different parameters are found to influence the flow and enhance mass and energy transfer in several heat configurations such as; Reynolds number (Re), nozzle geometry, spacing between jet exit and the impinging plate, jet impinging angle and the flow regime at the jet exit. There are a few studies that deal with heat transfer of a flow impinging on a rotating disk due to complexity of the flow structure and the challenges to conduct in-depth experimental investigation. Most studies present profiles of heat transfer coefficients, mean velocity and turbulence rates of the impinging flow. Many researches have reported that the LES can predict heat transfer and flow field data for different impinging angles to study the feedback mechanism between the nozzle and the plate.

The influence of pressure on the optical properties of nanostructured tetragonal Cu2Sb has been investigated jointly by experimental Raman spectroscopy (RS) and theoretical first-principles calculation based on density functional theory (DFT) varying pressure from zero (ambient condition) to 45 GPa. The DFT determined pressure dependence of the Raman active modes and the mode-Gruneisen parameters for each Raman mode are found to be in excellent agreement with those experimentally determined. Comparison of the pressure evolution of the experimental Raman data with those of DFT has allowed us to make the proper assignment of optical phonon modes.

Increasing energy demand, together with environmental concerns, results in a significant tendency toward the research and development of renewable systems and particularly solar energy. Locating in the sunbelt of earth, Iran has great solar potential. However, due to the noticeable amount of dust activities in the Middle East, there are several challenges in the way of development of the photovoltaic systems. The current article provides a comprehensive literature review on the photovoltaic status in Iran regarding the climate conditions, photovoltaic development potentials, energy policies within the country, and photovoltaic experiences. A regionally focused review of the conducted works is provided to investigate the effect of dust activities on the output performance of photovoltaic systems. A focus on dust origins, frequency, and specifications is a priority in order to analyze its impacts on the performance of photovoltaic systems. Furthermore, a review of cleaning methods to overcome the dust deposition problem is provided. The comprehensive literature review conducted in this article is represented to researchers, designers, and engineers dealing with photovoltaic systems in regions with dust problems such as the Middle East and particularly Iran.

Accepté dans Journal of Environmental Engineering - ASCE; International audience; The aim of this paper is to propose a step by step method to establish and validate a relevant, dynamical model of the activated sludge process for paper mill industry. The model is established by considering the specificities of the effluent to be treated. It uses the Biochemical Oxygen Demand (BOD) measurement, which allows a direct correlation between the state variables of the model and the measurements. This model is validated on a pilot plant of semi-industrial size fed with industrial paper mill effluents. The parameter estimation is based on an analysis of the sensitivities. Theresults are compared with a model based on Chemical Oxygen Demand (COD) partitioning which is issued from the simplification of the Activated Sludge Model n°1 (ASM1) model. Finally, the model dealing with BOD measurements not only shows the best performances but is also the easiest to implement, overcoming one main obstacle to efficient monitoring and control in paper mill wastewater treatment plants.