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Biomimetic actuators are typically constructed as functional bi- or multilayers, where actuating and resistance layers together dictate bending responses upon triggering by environmental stimuli. Inspired by motile plant structures, like the stems of the false rose of Jericho (Selaginella lepidophylla), we introduce polymer-modified paper sheets that can act as soft robotic single-layer actuators capable of hygro-responsive bending reactions. A tailored gradient modification of the paper sheet along its thickness entails increased dry and wet tensile strength and allows at the same time for hygro-responsiveness. For the fabrication of such single-layer paper devices, the adsorption behavior of a cross-linkable polymer to cellulose fiber networks was first evaluated. By using different concentrations and drying procedures fine-tuned polymer gradients throughout the thickness can be achieved. Due to the covalent cross-linking of polymer with fibers, these paper samples possess significantly increased dry and wet tensile strength properties. We furthermore investigated these gradient papers with respect to a mechanical deflection during humidity cycling. The highest humidity sensitivity is achieved using eucalyptus paper with a grammage of 150 g m⁻² modified with the polymer dissolved in IPA (~13 wt%) possessing a polymer gradient. Our study presents a straightforward approach for the design of novel hygroscopic, paper-based single-layer actuators, which have a high potential for diverse soft robotic and sensor applications.

Bio-based monomers represent the future market for polymer chemistry, since the political economics of different states promote green ventures toward more sustainable materials and processes. Industrial pulp and paper processing represent a large market that could advance the use of by-products to avoid waste production and reduce pollution. Lignin represents the most available side product that can be used to produce a bio-based monomer. This review is concentrated on the possibility of using bio-based monomer derivates from pulp and the paper industry for UV-curing processing. UV-curing represents the new frontier for thermoset production, allowing a fast reaction cure, less energy demand, and the elimination of solvent. The growing demand for new monomers increases research in the environmental field to substitute for petroleum-based products. This review provides an overview of the main monomers and relative families of compounds derived from industrial processes that are suitable for UV-curing. Particular focus is given to the developments reached in the last few years concerning lignin, rosin and terpenes and the related possible applications of these in UV-curing chemistry.

Fallopia japonica is a plant, native to East Asia, Japan, China and Korea, but in North America and Europe it is classified as invasive species. The root system and strong growth of these plants can damage buildings, streets, paving, retaining walls etc. It forms thick colonies, which crowd out other herbaceous species. In our project it was found out that the stem biomass of Fallopia japonica contains 40 percent of cellulose, which is comparable to the raw materials from which paper fibers are typically produced. With chemical and mechanical procedures and treatments, the fibers from Fallopia japonica were prepared and successfully the packaging paper has been produced. Generally, paper is widely used in packaging applications and it is considered as environmentally friendly substrate. It consists of a porous cellulose structure, composed of long-chain molecules in a crystalline state with amorphous regions in-between. Due to hydrophilic nature of cellulose and fiber network porosity, water barrier properties are limited. Conventional coatings that are used to improve water resistance, involve synthetic polymers such as polyethylene, rubber latex, polyvinyl alcohol etc. Natural renewable polymers have been the focus of many researches in recent years. Paper coatings are also commonly used with wax, but the recyclability of laminated and waxed papers is limited due to the separation from the paper, which is connected to the environmental issues. In this study biodegradable coating such as polysaccharide chitosan, was applied to paper made from Fallopia japonica. Namely, non coated paper from Fallopia japonica has high hydrophilic character and therefore it is not suitable for all packaging products. The aim of the research was to investigate the influence of different concentrations of chitosan in coating solution (5 and 10% w/w) on the physical and mechanical properties of the mentioned paper substrate. The water and moisture resistance of the coated paper substrates were determined via Cobb60 value tests, water vapor permeability and moisture. Scanning electron microscopy (SEM) was used to evaluate the effect of coating on the microstructures and the porosity of the paper. The results showed the compatibility of chitosan and paper substrate. Tensile properties of the coated paper has given promising results already at lower concentration (5%) of chitosan. Tensile strength and elongation at break increased, mainly by connectedness of chitosan matrix and polymer chain interactions. With thermogravimetric analysis (TGA) thermal stability and weight changes were detected at coated paper. A high weight loss of 20%, between 300°C and 400°C was detected at 5% and 10% chitosan coated paper, due to the degradation of chitosan main chains. The coated papers possessed better thermal, mechanical and water resistant properties. Considering the biobased nature of the coating and used paper substrate, the procedure can offer environmentally friendly and sustainable solution toward new packaging material. Using a Fallopia japonica as a source for the paper fibers, the need for the wood fibers could decrease and at the same time, the negative impact on the environment could reduce.

The paper production is developed throughout the world, therefore, more paper sludge waste (PSw) is accumulating. The aim of this work was to determine the properties of PSw burned at 900 °C and its impact on physical–mechanical properties of cementitious matrix and evaluate its usage/utilization possibilities in cementitious materials. For the implementation of the aim, cement-based specimens were prepared and their –mechanical properties were determined. Specimens from five compositions were formed, with 2.5%, 5%, 7.5%, and 10% of the cement by weight replaced with PSw. When 5% of the cement was replaced with PSw, the compressive strength increased by approximately 7%, although density and ultrasound velocity slightly decreased (up to 1.5%). When 7.5% PSw was added, the compressive strength of the specimens decreased. To summarize, it can be stated that up to 5% PSw may be utilized/used for the preparation of cementitious mixtures. The usage of the waste allows environment conservation, reduced amount of cement in mixtures, and improvement of properties of cementitious materials., This article belongs to the Proceedings of Innovations-Sustainability-Modernity-Openness Conference (ISMO’19), Bialystok, Poland, 22–23 May 2019

This work is focused on the use of line-scan thermography (LST) method for the inspection of an ancient book cover. Three widely used image post-processing techniques (i.e., pulsed phase thermography, partial least square thermography and principal component thermography) were applied to the acquired thermal sequences. Flash thermography (FT) anticipated the LST results in order to have a comparison of the results. It was concluded that LST is an effective technique for paper-based materials, and it can additionally provide a higher image contrast if compared to classical FT technique.

This work reports for the first-time integration of continuous microfluidic channels to the paper-based electro-osmotic pumps (EOPs) with liquid bridges. In addition, 0.2 μm pore sized cellulose acetate (CA) membrane filter is used to eliminate pressure-driven flow instead of filter paper which is common in paper microfluidics and has an average pore size of 10 μm. A factor of 57 increase in hydraulic resistance is achieved with the new paper. Fabrication of the pumps and microfluidic channels using paper, wax, adhesive film and PMMA plates is explained. Volumetric flow rate of 19 nL/min is achieved in the microfluidic system with 61 V/cm electrical field magnitude applied to DI water. The capability of the integrated system is shown with precise liquid motion in a Y-shaped microfluidic channel integrated with two EOPs.

Paper-based microfluidic technology is a relatively new field of research that provides low-cost platforms and sensors for point-of-care diagnostics. While the majority of research in this field has been for biomedical applications, more and more paper-based devices and platforms are being designed and developed for environmental applications, such as water quality monitoring and assessment. One such application is the detection of nitrate in water samples. Colorimetric detection of nitrate by paper-based devices using the Griess assay requires the reduction of nitrate to nitrite before undergoing the reaction. In this paper, we measured the performance of a paper-based dip strip for detecting nitrate and nitrite by calculating its limit of detection and limit of quantification. We also calculated the reduction efficiency of vanadium (III) chloride in the dip strip for detecting nitrate. Our results show that the reduction time of nitrate via vanadium (III) chloride is much longer than that when using zinc microparticles. Our results also show that the performance of the dip strip using vanadium (III) chloride for nitrate detection is not as good as more intricate paper-based devices that have a separate reaction zone with zinc microparticles. The limits of detection and quantification calculated were 3.352 and 7.437 ppm, and the nitrate reduction efficiency varied over the range of nitrate concentrations tested.

This Special Issue will publish selected papers from the International Symposium on Thermal Effects in Gas flow in Microscale ISTEGIM 2019 - A MIGRATE Event (http://www.istegim.eu/), 24-25 October 2019, Ettlingen, Germany. MIGRATE (www.migrate2015.eu) is a H2020 Marie Sklodowska-Curie European Training Network, intended to address some of the current challenges to innovation that faces European industry with regard to heat and mass transfer in gas-based micro-scale processes. This network of 10 participants and 6 associated partners coming from all over the European Community covers different aspects of enhanced heat transfer and thermal effects in gases: from modelling of heat transfer processes and devices, development and characterization of sensors and measurement systems for heat transfer in gas flows as well as thermally driven micro gas separators, to micro-scale devices for enhanced and efficient heat recovery in environmental, transport, telecommunications and energy generation. The MIGRATE Project presents his 2-day symposium, ISTEGIM19, during which the members of the MIGRATE network will showcase the main achievements of the project. The program will include keynote lectures, invited lectures and contributed papers.

Results are presented regarding the development of recycled paper based impedance biosensors with screen printed interdigitated electrode structures (IDES). The sensors show a response to increasing salt concentrations in the range 30–100 mM NaCl. To prove the feasibility of using recycled paper, biofunctionalization with a glucose sensitive enzyme mixture was performed by inkjet printing. The quantification of the glucose sensitive colour change reaction in paper was investigated and a trend is found in the range of 6–90 mg/dL. Subsequently, measurements with a wireless electronic readout system were performed on an electrochemical assay showing a decrease of the normalized sensor response dependent from the glucose concentration in the range 0–80 mg/dL.

Paper-based microfluidics as a promising and powerful platform shows great potential in the past decades1-4. As a crucial and essential function component to control fluid transport, the valve plays an important role in fluid manipulation, and enhancing the fluidic capability on μPADs. This paper describes a novel strategy to fabricate the movable valve on the paper-based microfluidic devices to manipulate capillary-driven fluids. The movable valve fabrication is firstly realized using hollow rivets as the holding center to control the paper channel in different layer movement that results in the channel's connection or disconnection. The relatively simple valve fabrication procedure is robust, versatile and compatible to the different levels of complexity μPADs. It is remarkable that the movable valve can be convenient, and free to control fluid without the timing setting that advantages make it user-friendly to the untrained users to carry out the complex multi-step operations. To verify the performance of the movable valve, several different designs of μPADs were tested and obtained with satisfactory results. In addition, in the proof-of-concept enzyme-linked immunosorbent assay (ELISA) experiments, we demonstrate the use of these valves in μPADs for the successful analysis of the samples of carcino-embryonic antigen (CEA) that showed good sensitivity and reproducibility. We hope this technique will open new avenues for the fabrication of paper-based valve in an easily adoptable and widely available way on μPADs and provide potential point-of-care applications in the future.

Paper-based microfluidics have gained widespread attention for use as low-cost microfluidic diagnostic devices in low-resource settings. However, variability in fluid transport due to evaporation and lack of reproducibility with processing real-world samples limits their commercial potential and widespread adoption. We have developed a novel fabrication method to address these challenges. This approach, known as “Microfluidic Pressure in Paper” (μPiP), combines thin laminating polydimethylsiloxane (PDMS) membranes and precision laser-cut paper microfluidic structures to produce devices that are low-cost, scalable, and exhibit controllable and reproducible fluid flow dynamics similar to conventional microfluidic devices. We present a new μPiP DNA sample preparation and processing device that reduces the number of sample preparation steps and improves sensitivity of the quantitative polymerase chain reaction (qPCR) by electrophoretically separating and concentrating nucleic acids (NAs) continuously on paper. Our device was assembled using two different microfluidic paper channels: one with a larger pore (25 microns) size for bulk fluid transport and another with a smaller pore size (11 microns) for electrophoretic sample concentration. These two paper types were aligned and laminated within PDMS sheets, and integrated with adhesive copper tape electrodes. A solution containing a custom DNA sequence was introduced into the large pore size paper channel using a low-cost pressure system and a DC voltage was applied to the copper tape to electrophoretically deflect the solution containing NAs into the paper channel with the smaller pore size. Samples were collected from both DNA enriched and depleted channels and analyzed using qPCR. Our results demonstrate the ability to use these paper devices to process and concentrate nucleic acids. Our concentration device has the potential to reduce the number of sample preparation steps and to improve qPCR sensitivity, which has immediate applications in disease diagnostics, microbial contamination, and public health monitoring.

Redox cycling is a phenomenon that occurs for redox species due to close interelectrode distance. [...]

Breath analysis is an attractive method for chronic diseases because it offers noninvasive, point-of-care diagnostics. [...]

Natural rubbers are characterized by extremely high molecular weight that might be beneficial in the formation of a protective barrier layer on paper substrates, providing good cohesive properties but limited adhesion. In parallel, the thermal properties of natural rubber with extremely low glass transition temperature might give the opportunity for good sealability. Therefore, natural rubbers can be good candidates to serve as an alternative ecological binder in paper coatings for water and grease barrier resistance. In order to be able to tune the surface properties of the paper coating, the effect of different additives are evaluated on rheological properties, thermo-mechanical properties and final surface properties of a paper coating. The additives are selected in parallel with common practice for paper industry, including talc, kaolinite clay and a type of organic nanoparticles, which are all added in the range of 5 to 20 wt.-%. Depending on the selected type of natural rubber, the dispersibility range (i.e., dispersive and distributive mixing) of the additives in the latex phase highly varies and is mainly determined by the molecular weight profile of the rubber. However, an optimum selection of viscosity range allows to obtain homogeneous mixtures without the need of surface modification of the additives. After bar-coating the latex mixtures on paper substrates, the drying properties of the composite coatings are followed by thermo-analytical evaluation and spectroscopy illustrating the influences of selected additives on the vulcanization process of the coating. In particular, the latter most efficiently improves in presence of nanoparticle fillers and highly increases the mechanical properties of the coating: the coating hydrophobicity can be successfully increased while in parallel reducing the adhesive surface properties.

After successful preparation of master batch formulations including polyhydroxybutyrate (PHB) and fibrillated cellulose additives, the compositions with different types and concentrations of fillers were used for the deposition of a coating on packaging paper grades, by using compression moulding in a hydraulic press. The resulting paper coatings are considered to provide a green solution for the production of protective barrier layer films with tunable hydrophobicity and oxygen barrier resistance. The processing of the nanocomposites into flat and homogeneous coatings was optimized for different conditions of moulding temperature and times, in particular, the flow conditions of the coating under pressing in contact with the substrate strongly depends on the presence of fillers. The effects of filler types on adhesion of the coating at the paper/polymer interface were investigated and the poor adhesion of native PHB coatings was tremendously improved after hydrophobic surface modification of the nanocellulose fillers. The inclusion of a wax and nanoparticles attached to the nanocellulose fiber surface enhanced the flowing properties of the coating by eliminating fiber agglomeration in contact with the paper substrate and reducing the effects of fiber pull outs. Therefore, hydrophobic fiber modification is necessary to obtain a homogenous dispersion during compressing moulding of coating materials for paper applications. Furthermore, the effect of processing on the final crystallinity of the master batches, films and paper coatings is presented by considering the reduction in degree of crystallinity for coatings in contact with a paper substrate owing to the surface confinement of crystallization processes. On the other hand, also the time-effects of secondary crystallization of the coatings as a function of aging time were lower for the coatings as compared to the free-standing films, in relation with the reduction of molecular mobility of the polymer chains under confined conditions.

The process of bonding and adhesives are an important part of human life from the earliest times. Over the years, a development has evolved. Natural adhesives were increasingly replaced by synthetic, which allowed to obtain more permanent weld and glue together different types of materials. Despite the emergence of new industrial sectors which allowed to connect components such as soldering, welding, thermal bonding, rivets, screws or pins gluing process did not lose in significance. People are willing to use the features and ease of use adhesives. Ecological aspects, however, pay attention to the safety of the environment. Decreasing non-renewable sources and the growing amount of waste affects the market, on which to a greater extent firms appear with environmentally friendly technologies. An important field of biodegradable polymers are produced from renewable raw materials that do not affect negatively the environment. Nowadays, more and more research is conducted to increase the scope of their use. The experimental section presents a method to prepare polylactide paper adhesives and the effects of additives on its properties. The first part a review of the latest scientific and patent literature towards polylactide biocomposite adhesives. This review shows a lack of studies on polylactide adhesives in the literature. This led to a series of experimental studies related to the selection of appropriate adhesive formulations, as well as additives favorably affecting the strength of the glued joints. The object of the study were the four compositions with the same concentration (polylactide dissolved in chloroform - primary composition, the composition containing pigments, the composition containing the essential oil and the composition with corn flour). The resulting compositions were subjected to a series of experimental studies such as: rheological tests including measurements of viscosity and thixotropy, peel strength, wettability and penetration, content of solids and creep tests. The lifetime of adhesives were determined, and we finally propose a method and the respective conditions for their long-term storage.

The drying process of paper has many production parameters that can influence both the energy consumed and the characteristics of paper produced. It was found that most of the previous studies conducted on this process assume that the conditions of the facilities are always appropriate. The control of the variables associated with air circulating inside the drying hood is essential to obtain a paper with adequate quality and obtain low ratios of energy consumption and CO2 emissions. This article proposes a new indirect method based on the study of the enthalpy of the airflows inside the production hall and thermographic images that helps to analyze the maintenance state of the enclosure hood drying section in a general process, whereby it can also estimate the emissions and energy losses. The combined use of sensors and equipment has helped to identify energy losses and potential savings in CO2 emissions. The developed method is applied to a paper manufacturing plant that has ratios of energy consumption and CO2 emissions very close to the product benchmark set by the European Authorities. The study corroborates that it can be identified as a significant energy loss in paper making drying process. Analyzing facilities that are in apparently good maintenance conditions, leaks are evident. These energy losses are very significant compared with the theoretical energy consumption, and it can affect the paper moisture profile. The authors would like to acknowledge the financial support of the Spanish Ministry of Economy and Competitiveness, Project DPI2014-58007-R.

Introduction The emergence of new communication technologies inevitably raises questions about the extent to which existing media work will change as a result, and this is particularly true in the case of journalism, both for the news production and the news consumption (Deuze & Marjoribanks, 2009; Alqudsi-ghabra, Al-Bannai, T., & Al-Bahrani, 2011; Mitchelstein & Boczkowski, 2010). Different studies have been documented in discussing about whether online news will substitute or displace print newspapers (Ahlers, 2006; Althaus & Tewksbury, 2000; Gentzkow, 2007; Newell, Pilotta, & Thomas, 2008), whether the internet provides a platform through which networked individuals can form a “Fifth Estate” (Dutton, 2009; Baum & Groeling, 2008), and whether the media digitization has affected journalistic norms and practices (Deuze, 2003, 2005; Lewis, Kaufhold, & Lasorsa, 2010). However, most of these studies focused on the analysis either about the online version of existed media (print newspapers or TV) or the role played by social-media platform (i.e. Twitter or Weibo) into the journalistic practices. Huffington Post, the American online news aggregator, which was the first commercially run digital media enterprise won a Pulitzer Prize in 2012, expanded its business largely since 2011 and opened new branches in main European countries (i.e. U.K., France, Germany, Italy, Spain), Asia (Japan, South Korea), and Latin America (Brazil). Established as a commentary blog in 2005, Huffington Post has grew to become one of the most influential original-produced online news source in a global context nowadays. The Paper (Pengpai Xinwen in Chinese), is a new Chinese online news platform established in July, 2014. Different from the origin of Huffington Post, The Paper is a “new media” project directed by the Shanghai United Media Group (state-owned media), however, it shares the same function as Huffington Post as an original-produced online news source targeted on different levels of digital media market (i.e. Web, APP, Wap, and other social media platform like Weibo and Wechat). Not so many researches have been made yet to investigate case studies of this kind of original-produced “online newspaper”, and even less comparative analyses were conducted to observe the same challenges but different solutions those platforms encounter and manage today across nations—especially under the West-East comparative context. And this paper is thus designed to fill in this gap. Methods Under the theoretic framework of comparative media system studies (Hallin & Macini, 2004; Zhao, 2011) and comparative journalism studies (Rantanen, 2010; Hanitzsch et al, 2011), this paper takes the approach of media political economy to discuss the role played by the state, the market and the audience in Huffington Post and The Paper. Some critical analyses on media content are also equipped for detailed understanding on the news frames (generic news frames and issue-specific frames) used in Huffington Post and The Paper. Results and Discussion The partisan characteristic (Huffington case in Europe) V.S. the role of the state (The Paper in China). The development of Huffington Post in the European case was especially embedded with partisan characteristic from the beginning. Such as the French version of Huffington was in partnership with Le Monde, the German version of Huffington was in partnership with Focus, thus the “Left-wing” orientation of Huffington Post-France and the “Liberal-conservative” orientation of Huffington Post-Germany did impact the news coverage (especially in the French case). The Paper, as a successful experiment of “new media” platform from state-owned media group, has been testing the bottom line of the Communist Party by utilizing its flexibility of providing online-content and its openness from the support of local Shanghai government, however, it still meets limits by receiving pressures from the central government on certain politic news topics. The market/users-driven content production (crowdfunding case in Huffington) V.S. the politics/users-driven content production (the liberal orientation on The Paper). In this part the author discussed the crowd-funding case in Huffington to follow the coverage about Michael Brown, to see whether this example could provide original online newspaper an alternative way to follow public-interest with a focus on the “market”; and also discussed the anti-corruption case in Peng Pai to understand its dilemma between Chinese public interests and the Chinese authorities with a focus on the “politics”. Next “New-York times” V.S. next “Nan Fang Zhou Mo”: The construction of news credibility and media accountability are crucial questions for original-produced online newspapers. Huffington Post provided a positive case for this constructive process as it received Pulitzer Prize in the year of 2012 for one of its senior military correspondent, while Peng Pai is still struggling of identifying itself as a successor or an opponent of “South Genre”, which was recognized widely for its liberal orientation that contributes to public democratic debate and the formation of civil society in China. References and Notes Ahlers, D. (2006) News consumption and the new electronic media. Harvard International Journal of Press-Politics, 11(1), pp.29–52. Alqudsi-ghabra, T. M., Al-Bannai, T., & Al-Bahrani, M. (2011) The Internet in the Arab Gulf Cooperation Council (AGCC): Vehicle of Change. International Journal of Internet Science, 6(1), pp.44–67. Althaus, S., & Tewksbury, D. (2000) Patterns of Internet and traditional news media use in a networked community. Political Communication, 17(1), pp.21–45. Baum, M., & Groeling, T. (2008). New media and the polarization of American political discourse. Political Communication, 25(4), 345–365. Deuze, M. (2003) The web and its journalisms: Considering the consequences of different types of newsmedia online, New Media & Society, 5(2), pp.203-230. Deuze, M. (2005), What Is Journalism? Professional identity and ideology of journalists Reconsidered, Journalism, 6(4), 442-464. Deuze, M., & Marjoribanks, T. (2009) Newswork, Journalism, 10(5), pp.555-561. Dutton, W.H. (2009). The Fifth Estate emerging through the network of networks. Prometheus, 27(1), pp.1–15. Gentzkow, M. (2007). Valuing new goods in a model with complementarity: Online newspapers. American Economic Review, 97(3), pp.713–744. Hallin, D.C. & Mancini, R.M. (2004) Comparing Media Systems: Three Models of Media and Politics. Cambridge University Press Hanitzsch et al (2011) Mapping Journalism Cultures Across Nations: A comparative study of 18 countries. Journalism Studies, Volume 12, Issue 3, pp. 273-293 Lewis, S.C., Kaufhold, K. & Lasorsa, D.L. (2010) Thinking about citizen journalism: The philosophical and practical challenges of user-generated content for community newspapers, Journalism Practice, 4(2), pp.163-179. Mitchelstein, E., & Boczkowski, P. J. (2010) Tradition and transformation in online news production and consumption, In Dutton, W. H. (Eds.), The Oxford handbook of Internet studies. Oxford: Oxford University Press. Newell, J., Pilotta, J. & Thomas, J. (2008). Mass media displacement and saturation. International Journal on Media Management, 10(4), pp.131–138. Rantanen, Terhi (2010) Methodological inter-nationalism in comparative media research: flow studies in international communication In: Roosvall, Anna and Salovaara-Moring, Inka, (eds.) Communicating the Nation: National Topografies of Global Media Landscapes. Nordicom Publications, Gothenburg, pp.25-39. Zhao, Y.Z. (2011) The Challenge of China: Contribution to a transcultural political economy of communication for the twenty-first century. In Wasko, J. et al. (Eds.) The handbook of Political Economy of Communications, Wiley-Blackwell publication, pp.558-582.