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In the production of pigment-coated paper or paperboard, the method and rate of drying of the coating will significantly influence the print quality of the finished product. Improper drying during initial st sages can cause binder migration that leads to its non-uniform concentration on the surface of the coating. Such effect causes print mottle, and is a primary reason for poor print quality. The location at which binder immobilization has occurred is called the Gel Point. An on-line fiber optic sensor system has been applied to continuously monitor the location of the Gel Point. Each sensor consists of a light source, an optical fiber for delivering the radiation, two optical fibers for diffuse and specular radiation monitoring and two detectors. The ratio R between diffuse and specular signals indicates coating conditions. A system description and experimental results are presented. The Gel Point measurement system has show that is provides a sensitive measurement of the gel point location, as it is affected by machine speed, coat weight, incoming substrate moisture levels and drying energy and can predict print mottle. This provides the paper maker with a completely independent method for monitoring the coating drying process.

The paper industry has long had a need to better understand and control its papermaking process upstream, specifically at the wet end in the forming section of a paper machine. A vision-based system is under development that addresses this need by automatically measuring and interpreting the pertinent paper web parameters at the wet end in real time. The wet-end characterization of the paper web by a vision system involves a four-dimensional measurement of the slurry in real time. These measurements include the two-dimensional spatial information, the intensity profile, and the depth profile. This paper describes the real-time depth profile measurement system for the high-speed moving slurry. A laser line-based measurement method is used with a high-speed programmable camera to directly measure slurry height. The camera is programmed with a profile algorithm, producing depth data at fast sampling rates. Analysis and experimentation have been conducted to optimize the system for the characteristics of the slurry and laser line image. On-line experimental results are presented.

Therapeutic drug monitoring (TDM) contributes to safe and effective pharmacotherapy in clinical fields. A simple, rapid, low-cost, and minimally-invasive drug measurement method attracts much interest for point-of-care TDM. Tear fluids can be collected minimally-invasively compared to blood sampling and there is a correlation between a drug concentration in tears and that in bloods. Surface enhanced Raman spectroscopy (SERS) with paper-based substrate is useful for point-of-care TDM owing to inexpensiveness and high-sensitivity. Paper is also a safe tear collection tool. Then we are studying on a paper-based SERS of tear specimen for point-of-care TDM. In this paper, to improve sensitivity in measuring drug concentration in tear fluids, we fabricated a SERS substrate by coating gold nano-rods on a paper substrate and evaluated whether the fabricated substrate can enhance Raman scattering. Sodium phenobarbital (PB), an anti-convulsant agent, was used as a target. In experiment, the fabricated substrate indicated the lower detection limit of PB in a solution than a plain paper substrate. This result showed the potential of the paper based SERS substrate to measure drug concentration in tears simply and inexpensively.

By combining the physical principles behind the nastic plant movements and the rich designs of paper folding art, we propose a new class of multi-functional adaptive structure called fluidic origami cellular structure. The basic elements of this structure are fluid filled origami "cells", made by connecting two compatible Miura-Ori stripes along their crease lines. These cells are assembled seamlessly into a three dimensional topology, and their internal fluid pressure or volume are strategically controlled just like in plants for nastic movements. Because of the unique geometry of the Miura-Ori, the relationships among origami folding, internal fluid properties, and the crease bending are intricate and highly nonlinear. Fluidic origami can exploit such relationships to provide multiple adaptive functions concurrently and effectively. For example, it can achieve actuation or morphing by actively changing the internal fluid volume, and stillness tuning by constraining the fluid volume. Fluidic origami can also be bistable because of the nonlinear correlation between folding and crease material bending, and such bistable character can be altered significantly by fluid pressurization. These functions are natural and essential companions with respect to each other, so that fluidic origami can holistically exhibit many attractive characteristics of plants and deliver rapid and efficient actuation/morphing while maintaining a high structural stillness. The purpose of this paper is to introduce the design and working principles of the fluidic origami, as well as to explore and demonstrate its performance potential.

As a bio/chemical sensing technique, surface enhanced Raman spectroscopy (SERS) offers sensitivity comparable to that of fluorescence detection while providing highly specific information about the analyte. Although single molecule identification with SERS was demonstrated nearly 20 years ago, today a need exists to develop practical solutions for point‐of‐sample and point‐of‐care SERS systems. Recently, we demonstrated the fabrication of SERS substrates by inkjet printing silver and gold nanostructures onto paper and other microporous membranes. Using these devices, we have been able to achieve detection limits comparable to conventional nanofabricated plasmonic substrates. Furthermore, we leverage the fluidic properties of paper to enhance the performance of the SERS devices while also enabling unprecedented ease of use. Here we report the use of inkjet‐fabricated paper SERS substrates as a detection device for biological macromolecules in an easy‐to‐use format with a low number of steps. The targeted biomarker is specifically detected with SERS through a single step competitive displacement, which dramatically reduces the number of steps as compared to conventional assays. Moreover, we further improve the usability of the assay by incorporating a paper SERS device with a fluidic cartridge format. The wicking nature of the paper sensor eliminates manual sample application steps and is much simpler than the world‐to‐chip interface of microfluidic devices. The introduction of this paper‐based SERS assay is a significant step towards highly sensitive, low‐cost, and, importantly, easy to use multiplexed biological assays.

There are two main challenges in producing a robust, paper-based analytical device. The first one is to create a hydrophobic barrier which unlike the commonly used wax barriers does not break if the paper is bent. The second one is the creation of the (bio-)specific sensing layer. For this proteins have to be immobilized without diminishing their activity. We solve both problems using light-based fabrication methods that enable fast, efficient manufacturing of paper-based analytical devices. The first technique relies on silanization by which we create a flexible hydrophobic barrier made of dimethoxydimethylsilane. The second technique demonstrated within this paper uses photobleaching to immobilize proteins by means of maskless projection lithography. Both techniques have been tested on a classical lithography setup using printed toner masks and on a lithography system for maskless lithography. Using these setups we could demonstrate that the proposed manufacturing techniques can be carried out at low costs. The resolution of the paper-based analytical devices obtained with static masks was lower due to the lower mask resolution. Better results were obtained using advanced lithography equipment. By doing so we demonstrated, that our technique enables fabrication of effective hydrophobic boundary layers with a thickness of only 342 μm. Furthermore we showed that flourescine-5-biotin can be immobilized on the non-structured paper and be employed for the detection of streptavidinalkaline phosphatase. By carrying out this assay on a paper-based analytical device which had been structured using the silanization technique we proofed biological compatibility of the suggested patterning technique.

Food-borne pathogens such as Listeria monocytogenes have been recognized as a major cause of human infections worldwide, leading to substantial health problems. Food-borne pathogen identification needs to be simpler, cheaper and more reliable than the current traditional methods. Here, we have constructed a low-cost paper biosensor for the detection of viable pathogenic bacteria with the naked eye. In this study, an effective isothermal amplification method was used to amplify the hlyA mRNA gene, a specific RNA marker in Listeria monocytogenes . The amplification products were applied to the paper biosensor to perform a visual test, in which endpoint detection was performed using sandwich hybridization assays. When the RNA products migrated along the paper biosensor by capillary action, the gold nanoparticles accumulated at the designated Test line and Control line. Under optimized experimental conditions, as little as 0.5 pg/μL genomic RNA from Listeria monocytogenes could be detected. The whole assay process, including RNA extraction, amplification, and visualization, can be completed within several hours. The developed method is suitable for point-of-care applications to detect food-borne pathogens, as it can effectively overcome the false-positive results caused by amplifying nonviable Listeria monocytogenes.

This work addresses the study of repeatability of an optical laser system, previously implemented by our research team, for characterization of the fiber distribution and mass density of two paper samples with different characteristics. In the experiment that has been carried out in the current work, both paper samples were laser scanned by the system on a total of 16 times (4 times per day in 4 different days). The data acquired and registered during the experimental work, associated to both tested samples, were then processed and the obtained results showed that the optical system is precise.

Ink jet printability is rapidly becoming a requirement for all multipurpose office papers. These papers must have an optimized balance of properties so they can perform equally well under various printing methods such as xerography, ink jet, and thermal imaging. The office paper of today truly must be a multipurpose copy paper capable of providing good toner adhesion as well as controlled absorption of aqueous ink jet solutions. The demand for ink jet paper is increasing rapidly. The global market for cut-size ink jet papers will expand to nearly 1.4 million tons by the year 2000. By that time the global market for all cut-size multipurpose plain printing papers will grow to nearly twenty million tons. The ink jet printing process places a large volume of aqueous ink on the surface of a substrate. The manner in which the substrate handles that volume of ink determines in large part the quality of the print. Multipurpose office papers are composed chiefly of cellulose fibers, inorganic fillers, and chemical additives. All of these components affect the quality of the sheet as an ink jet substrate. The particle morphology, surface area, and surface treatment of PCC fillers affect the ink jet printability of multipurpose office papers. This paper focuses on results from pilot paper machine and commercial trials performed in an effort to turn 'plain' office papers into high quality multipurpose papers capable of meeting or exceeding ink jet print quality specifications.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Paper makers use many different synthetic and natural chemical additives for a variety of different reasons during the wet formation process. They are used to influence the efficiency of the formation process or to impart specific sheet properties. They are usually added (with the exception of pigments) at a level of around 0-5% by weight of the other components of the furnish and, because of their relatively high cost, they often represent a significant proportion of the total raw material costs - particularly for recycled grades where the fibre costs may be very low. When it is necessary to modify bulk sheet properties, as in the control of aqueous fluid penetration (internal sizing), the chemicals have to be added to the wet fibre suspension so that they become well distributed throughout the z-direction of the sheet. Chemicals which are added as a surface treatment to the dry sheet are usually only able to influence surface properties.

The composition of photographic color negative papers is reviewed. Information is presented on the potential detrimental effect of the polyethylene resin-coated (RC) paper support on the thermal stability of the silver halide element. Evidence is provided for the major role that the pH of the dry paper stock has in this effect. A mechanism for the detrimental photographic performance involving both the RC and the paper stock is proposed.

From the chemical point of view paper coatings are mainly polymer dispersions. Polymer dispersions are constituted in multitude fields, for example as dispersion coatings or adhesives. As far as no additional treatment is done, polymer materials as well as polymer agents contain non polymer, volatile organic components that may arise from: (1) incomplete polymerization of the applied monomers, (2) primary materials containing non polymerizable components, (3) undesirable side reactions during the synthesis. Requirements for the removal of volatile substances from polymer dispersion are given by several reasons: (1) low molecular substances deteriorate the product characteristics (viscosity, thermal stability and others), (2) in order to comply with legislative standards, volatile organic compounds have to be removed from dispersions, especially when applied to large surfaces (e.g. in surface refining in paper and leather industries as well as on coating). The removal of volatile organic compounds (deodorization) can be realized in continuous or discontinuous processes. In contrast to highly developed process technology, the process itself is not well understood, especially mass transport phenomena between the gas phase and the aqueous polymer dispersion are insufficiently and controversially discussed in the literature. Two processes, their advantages and disadvantages and the description by mathematical- mechanistic models are presented in this paper.

Uncontrolled growth of bacteria and fungi in the papermaking process adversely affects machine runability. How this growth influences factors in the finished sheet and sheet print properties is often overlooked, even though it can have a profound effect on printing characteristics. Many of the materials used in making paper coatings are excellent microbial nutrients. In addition to being nutrients, these compounds are critical to performance. For example, coatings made of poorly preserved clays can form a surface that has fine scratches caused by microagglomeration of the clay particles. This may be caused by microbial degradation of the dispersants in the clays. This paper explores these issues and discusses steps that can be taken to minimize these problems.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A methodology has been developed to digitize images from photographic color paper (reflection prints) and store the spectral information as a function of the three dye density basis functions inherent to the paper film type. The result is a highly accurate digitization of the spectral information at each spatial pixel that can be digitally stored with very little additional storage space over conventional RGB-type methodologies.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

IR monitoring is a basic tool for quality control and predictive maintenance in the paper industry. There are also other possible interests, e.g. measurements of temperature profiles of high speed production lines. The first possibility to use IR for the above mentioned use appears to be applications of glass heat treatment in on line production. At this time there is a lot of interest to be able to measure temperature profiles from a fast moving surface (e.g. in paper machines) with velocities like 10 - 20 m/s. Normal low speed line scanners typically give scanning speed of 50 Hz which in this case means 20 m/s/50 Hz equals 40 cm resolution. The obtained resolution is not normally high enough. To have more accurate vision from the studied surface IR camera line scanning was proposed to be a solution with line scanning frequencies of 8000 Hz which would provide resolution of 20 m/s/8000 Hz equals 0.25 cm between surface points. It is a well-known fact that all undesired frequencies in paper transfer systems disturb the uniform paper drying process which in some cases is the basic reason for low quality coating or even broken paper line. The possibility to detect these drying problems with IR frequency analysis will give a new way to control the paper drying process. With IR analysis it is possible to get information about temperature distributions along the paper track. Using a well established frequency analysis as a tool, the error estimations are obtained. In most cases an open-roll image from paper track is very desirable because there are no existing wide area measurement systems for this purpose. The careful analysis of this new method is given in the manuscript.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The expression 'Plain' paper was coined in the early days of electrophotography to distinguish the capabilities of the new dry toner based photocopying process which did not require a sensitized or special coated paper to produce an image. Currently 'Plain' paper is considered in the electronic printing industry, to be any uncoated paper, usually of the type used in office photocopying applications. It is assumed that all 'Plain' papers are identical or at least equivalent in their properties such that all papers will give equivalent print quality performance. Due to the wide availability and low price of 'Plain' papers, it is also considered desirable by vendors of electronic marking processes, that their technology be capable of producing good image quality on 'Plain' paper. The chemical and physical differences which can occur among 'Plain' papers are discussed with respect to the specific image quality and engine reliability requirements of the major nonimpact electronic marking technologies, including electrophotography and laser printing, electrographic and ionographic processes, thermal transfer and ink jet. Paper properties of interest include, smoothness, surface energy, electrical resistivity, porosity and aqueous and nonaqueous liquid adsorption. Color printing has added additional requirements to paper quality, if good image quality is to be achieved and maintained. Given the apparently conflicting requirements for some of the electronic marking technologies, it will be a challenge to define a single grade of paper which will produce optimum print quality for all electronic printing processes.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper, a novel self-heating composite material utilizing carbon nanotubes (CNTs) paper is designed and fabricated successfully. The carbon nanotube paper was prepared by multiple steps of CNTs dispersion and suspension filtration as shown in Fig1. a and characterized by scanning electron microscopy thermo gravimetric analysis nitrogen adsorption isotherms at 77K and so on. The surface of the as-prepared CNTs paper is smooth and very flexible. The conductivity of the CNTs paper could be regulated from 30 S/cm to 200 S/cm. The fabricating process of the self-heating is shown in Fig.1 b and the electric heating performance under different ambient temperature, power changing from 4.3W to 44.8W and wind speed ranging from 8m/s to 14m/s was discussed. In addition, the feasibility of the application in the deicing of the composite was simulated by the software of Fluent. The thermal behavior was discussed combining the experimental and simulated values, especially the temperature field distribution under different wind speed. The maximum heating rate can reach 2℃/s under different condition. The equilibrium temperature and energy consumption of the composite at different power compared with the commercial kanthal electric heating film were also investigated. The energy consumption of the self-heating material is less than the kanthal electric heating film to reach the same equilibrium temperature which may be caused by the difference of heat capacity. The experimental and simulated results indicate the electric heating performance of CNTs paper-based composite is superior to the commercial kanthal electric heating film and has feasibility in the field of deicing.

In this present study experimental and finite element analysis of cellulose based electro-active paper energy harvester is presented. Electro-active paper coated with metal electrode is a smart form of cellulose and exhibit piezoelectric effect. Specimens were prepared by depositing electrodes on both sides of the cellulose film. A 50 mm x 50 mm cellulose film coated with aluminum electrodes was bonded on 100 mm x 50 mm x 1 mm aluminum host structure. The voltage output to input acceleration frequency response across a load resistor of 1 MΩ is recorded by conventional energy harvesting experimental setup at the fundamental vibration mode of the EAPap cantilever beam. A coupled piezoelectric-circuit finite element model is developed in which load resistor is directly connected to energy scavenging device. Voltage output FRF is measured for the cases, without proof mass, and by adding a 2 grams proof mass near the tip of the cantilever. The experimental voltage FRF value is 7.6 V/g at 75.1 Hz and is improved to 13.8 V/g at 62.2 Hz when a stainless steel proof mass of 2 grams is added. The presented CPC-FEM model results agree reasonably well with the experimental results. Despite the fact that the electro-mechanical coupling coefficient of electro-active paper is lower than other available piezoelectric materials, it is biocompatible, cheap and naturally occurring polymeric material. It is also very flexible and posses similar piezoelectric characteristics such a PVDF which inspire to use EAPap in energy harvesting applications.

Paper based composite with semiconductor nanomaterial is a fascinating orgnic-inorganic hybrid composite that has improved properties of flexibility, biocompatibility and functionality. Cellulose Electro-Active Paper (EAPap) is a kind of paper electric device. To improve functionality of EAPap, ZnO is used as hybrid inorganic composition. Cellulose- ZnO hybrid nanocomposite (CEZOHN) is fabricated by seeding and growing ZnO on cellulose film with a simple chemical reaction. CEZOHN reveals not only electrical, eletromechanical behavior but also photoelectrical behavior. This paper reports specially photo-response and sensitivity of CEZOHN under several light source: UV light, sun and fluorescent light. The fabrication process is briefly introduced, and induced voltage, induced current under light source are investigated. Also, the ZnO effect of CEZOHN and its mechanism is studied and its possibility of application as photosensor, photodiode, photovoltaic device will be discussed.

With smart materials and adaptive structures being nudged into mainstream technology progressively, the smart composites are donning a predominant role as indispensable structures. Among these, the Ionic Polymer Metal Composites (IPMC), with their large bending deformation and relaxation characteristics at very low voltages are attractive as transducers in many areas of application. The actuation and sensing properties of IPMC have been sought after for various engineering functions. The paper focuses on combining the ionic polymer with multi-walled carbon nanotube Bucky paper electrodes to create an enhanced IPMC, and comparatively analyzes the different methodologies briefly discussing the electrode morphology and also compares the uniformity of the electrode plating obtained from the different processes. This paper also concentrates on making use of different ionic solutions for comparison such as to determine the most suited ion content within the solid electrolyte for effective IPMC actuation. This new functionally graded material is tested for its bending deformation, blocking force and the current consumption to prove the electromechanical efficiency of the Bucky paper IPMC. By studying the electromechanical properties of this smart composite actuator based on its actuation under different electric excitations, we can draw conclusions subsequently from the results of the comparison.

The appearance of translucent materials is strongly affected by bulk (or sub surface) scattering. For paper and carton board, lateral light propagation and angle-resolved reflection have been studied extensively but treated separately. The present work aims at modelling the BSSRDF of turbid media in order to study the angular variation of the reflectance as function of the lateral propagation within the medium. Monte Carlo simulations of the spatial- and angle resolved reflectance of turbid media are performed for different scattering and absorption coefficients, phase functions and surface topographies representative for uncoated paper grades. The angle-resolved radiance factor of turbid media is found to be function of the lateral light propagation within the substrate and both the reflected radiance factor and the fluorescence emission are found to be clearly non- Lambertian, although the latter clearly depends on the light absorption at the excitation wavelength. It is also suggested that the modelling of uncoated paper should not include surface scattering. The findings impact on the appearance of turbid media at different angles and make measurements of the lateral light propagation dependent on the instrument geometry.

This report describes a method for the creation and automatic content verification of low-cost self-verifiable paper documents. The image of an original document is decomposed to symbol templates and their corresponding locations. The resulting data is further compressed and encrypted, and encoded in custom designed high-capacity color barcodes. The original image and barcodes are printed on the same paper to form a self-verifiable authentic document. During content verification, the paper document is scanned to obtain the barcodes and target image. The original image is reconstructed from data extracted from the barcodes, which is then registered with and compared to the target image. The verification is carried out hierarchically from the entire image down to word and symbol levels. For symbol level comparison, multiple types of features and shape matching are utilized in a cascade. The proposed verification method is inexpensive, robust and fast. Evaluation on 216 character tables and 102 real documents achieved greater than 99% alteration detection rate and less than 1% false positives at the word/symbol level.

In this work, two optical systems previously designed and implemented by our research team, were used to enable the surface and bulk inspection of the ink-paper interaction by image analysis. Basically, the first system works by ejecting micro-liter ink drops onto the papers surface while monitoring the event under three different views over time. The second system is used for sectioning the paper samples through their thickness and to simultaneously acquire images of the ink penetration of each section cut. In the performed experiments, three black inks of different brands and a common copy paper were chosen, used, and tested with the two developed optical systems. Both qualitative and quantitative analyses were carried out at the surface level and in the bulk of the paper. In terms of conclusions, it was shown that the three tested ink-paper combinations revealed very distinct characteristics.

There are several parameters, which influence the characteristics of the final printed colors in digital printing. One of the most important one is the substrate (paper). In the present study, the effect of uncoated papers on the laser printed colors was investigated. For this purpose, three kinds of paper with the same grammage value of 80 and different whiteness and texture were selected. The effect of paper on the printer's reproducibility, light-fastness, color gamut and colorimetric characteristics of the final printed samples were studied for a Canon Laser Printer LBP-5050. It was found out that, the reproducibility of the printer is statistically dependent on the paper's type. The average of color change via exposing light is between 1.3 and 1.8 for different papers. The color difference caused by paper variation illustrates the effect of paper on the final printed colors. The texture properties of the papers were quantified with Edge Frequency technique as an appropriate texture analysis tool. A defined correlation between texture changes and color differences was obtained. Furthermore, the whiteness of the papers clearly affected the final printed colors.

Surface enhanced Raman spectroscopy (SERS) requires the analyte molecule to be close to the plasmonic surface in order to generate SERS enhancement. This limitation restricts the practical application of SERS to molecules that possess functional groups that interact strongly with gold or silver surfaces. Moreover, the identification of target analytes in a complex sample matrix is made even more difficult when interferents compete with the target for binding to the plasmonic surface, resulting in overlapping spectral signatures. In this work, we report a strategy to functionalize inkjet printed P-SERS substrates by strategically placing supramolecular structures (such as nucleic acid aptamers) onto the gold nanoparticles. This promotes the selective interaction of target molecules with the plasmonic surface, leading to improved sensor performance.

The first thermal paper technology was developed in the 1930s. Since then, thermal recording systems have branched into two main groups, two-component systems and heat-transfer systems. In the 1960s, the leuco dye system was developed by NCR. This type of system has been used mainly in thermal recording systems. The leuco dye system however has some drawbacks such as poor image stability and an artificial texture. In a recent development, a compound with an epoxy functional group was added to the thermal sensitive layer of a leuco dye thermal paper to obtain good stability. A special overcoat layer gives the product the texture of plain paper. In addition to this product, other special thermal papers have been developed, such as two-color thermal paper, IR readable thermal paper, high resolution thermal paper, and translucent thermal paper.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A multilayer Paper Analytical Device (PAD) is provided for detection of at least two chemical components indicative of a low quality pharmaceutical or dietary supplement product. A method for detection of at least two chemical components indicative of a low quality pharmaceutical or dietary supplement product is also provided that employs a multilayer PAD. A kit is provided for detection of at least two chemical components indicative of a low quality pharmaceutical or dietary supplement product that includes a multilayer PAD and instructions for using the kit.

Surface enhanced Raman spectroscopy (SERS) is a highly sensitive sensing technique, offering sensitivity comparable to that of fluorescence while providing structure-dependent analyte information. In recent years, we have developed an innovative optofluidic SERS substrate by inkjet printing metal nanoparticles onto paper. By virtue of generating a SERS substrate on cellulose, we gain a flexible SERS sensing device, as well as the ability to harness the intrinsic wicking properties of paper to enable both separation and concentration of analytes. Here we demonstrate the application of paper-chromatographic separation to allow on-substrate separation, concentration and discrimination. By using inexpensive single-labeled DNA probes in a typical PCR amplification, we obtain a mixture containing whole probes (negative result) and probes which have been hydrolyzed by the Taq polymerase (positive result). Leveraging the solubility differences between the whole and hydrolyzed probes and the cellulose separation matrix, we are able to perform a multiplexed interrogation of the targets. Notably, this does not require the use of dual labeled DNA probes (expensive) or multiple excitation sources and filter sets needed for a multiplexed fluorescence measurement (expensive and bulky). All SERS measurements are performed using a portable spectrometer and diode laser; in combination with a portable low-power DNA amplification system, this technique has the potential to be used for rapid on-site multiplexed genetic detection, without requiring complex optical equipment.

Recently direct thermal recording systems have become very popular and are increasingly used in various fields. Consequently, strong demand has arisen for a thermal paper that has good response to heat, the background and images thereon having high stability and a strong resistance to various chemicals and various solvents. Many attempts have been made to overcome the difficulties described above. However such attempts have had a tendency to lower response to heat and further to be insufficent with respect to the stability of solvents. Therefore, we have developed a new method for production of a heat sensitive layer having in itself high resistance to various solvents and also using specific new materials. The most important aspect of our new method consists in the use of specific developers with very low solubility in organic solvents and very strong developing activity. Originally, we intended to use the high developing power of zinc salicylate derivatives, these generally having a high solubility in solvents. But now our efforts have been concentrated on lowering the solubility of salicylate. Finally, we found some very specific salicylate that has a very poor solubility in almost all solvents. We have now succeeded in providing a much more reliable thermal paper which has stronger resistance to various kinds of chemicals.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The coating color for the direct thermal paper basically consists of the leuco dye, the cobr developer and the sensitizer. Blacking dyes to be used for thermal papers call for other practicable properties than the tone, such as storage stability, thermal sensitivity and white background. Since no universally accepted theory in choosing proper developer and sensitizer is available, however, selection will have to be conducted on the designer's experience. Such practical considerations as the stability of the recorded image and matching with the particular machine to be used for are important beside the chemical considerations.

In the recent times, cellulose-based Electro-Active Paper (EAPap) has been investigated to have electro-mechanical coupling and piezoelectric effects which are promising characteristics for a smart material. In this paper, the effects of electrodes of EAPap are investigated for vibration energy harvesting. Although piezopolymers have smaller value of electro-mechanical coupling constants as compared to the piezoceramics, but are very flexible, which motivates to use these materials as potential media for flexible energy harvesting. Cellulose based Electro-active papers are deposited with different metal electrodes like aluminum, gold and silver. The fabricated samples are tested with aluminum cantilever beam under an input excitation. The effects of area of electrodes are also investigated by comparing the output voltage at the different area of electrodes ranging from 400mm2 to 1200mm2. EAPap cantilever are tested at lowest resonant frequency and under varying acceleration amplitude to maximize the output voltage. From the experimental results, it is concluded that the potential of EAPap as a flexible energy harvester are very promising.

Many infectious diseases, as well as some cancers, that affect global health are most accurately diagnosed through nucleic acid amplification and detection. There is a great need to simplify nucleic acid-based assay systems for use in global health in low-resource settings as well as in settings that do not have convenient access to laboratory staff and equipment such as doctors’ offices and home care settings. In developing countries, unreliable electric power, inadequate supply chains, and lack of maintenance for complex diagnostic instruments are all common infrastructure shortfalls. Many elements of instrument-free, disposable, nucleic acid amplification assays have been demonstrated in recent years. However, the problem of instrument-free,1 low-cost, temperature-controlled chemical heating remains unsolved. In this paper we present the current status and results of work towards developing disposable, low-cost, temperature-controlled heaters designed to support isothermal nucleic acid amplification assays that are integrated with a two-dimensional paper network. Our approach utilizes the heat generated through exothermic chemical reactions and controls the heat through use of engineered phase change materials to enable sustained temperatures required for nucleic acid amplification. By selecting appropriate exothermic and phase change materials, temperatures can be controlled over a wide range, suitable for various isothermal amplification methods, and maintained for over an hour at an accuracy of +/- 1°C.

Lateral flow tests (LFTs) are well-suited for rapid point-of-care testing in low resource settings. The wicking action of the paper strip moves the sample and reagents through the device without a need for pumps, but LFTs are typically limited to tests that can be carried out in a single fluidic step. The materials from LFTs can be reconfigured to create paper networks that automatically carry out multi-step fluidic operations, while retaining the same easy-to-use format as a conventional LFT. Here, we describe basic principles of wicking and system-level behavior of paper networks by analogy to electrical circuits. We describe key design principles for a previously-developed 2D paper network (2DPN) and introduce an alternative linear paper network (Pseudo-1DPN) that takes advantage of system-level behavior to perform clean sequential fluid delivery while reducing device running time.

Conventional thermal paper utilizes an electron-donating colorless dye and an electron- accepting developer which react to give a colored image. To improve the image stability, various methods have been proposed. However, there has been no study on the prediction of the image stability. We found that under a defined condition of the thermal acceleration test, the Arrhenius Plot of the fading gives a straight line, and the predicted value gives good coincidence with the value obtained by actual aging. This report presents the outline of the method for prediction and the coincidence of the result of the test method with that obtained by actual aging.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Wet paper code is a complex model which mainly used in the field of image coding. This paper is based on the wet paper code model and human visual system, and constructs a new wet paper code steganographic method. According to the regional complexity and other characteristics of the host image, the secret bits are adaptively embedded into wavelet coefficients of image subbands with wet paper code. Secret information receivers do not need to know the specific method of secret writing, just do a simple matrix multiplication operation and can extract the secret information, which in many ways to improve the security of the steganographic algorithm. The experiments show that the method has good visual invisibility and resistance of active steganalysis attacks.

We report a novel surface enhanced Raman Scattering (SERS) substrate platform based on a common filter paper adsorbed with plasmonic nanostructures. Paper based SERS substrate overcomes many of the challenges associated with conventional SERS substrates based on rigid substrates such as silicon and glass. The paper-based design results in a substrate that combines all of the advantages of conventional rigid and planar SERS substrates in a dynamic flexible scaffolding format. We discuss the fabrication, physical characterization and SERS activity of our novel substrates using non-resonant analytes.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

This paper presents the influence of reaction time for the thickness and particle density of ZnO layer. Paper-like ZnOCellulose hybrid nanocomposite was fabricated using a low temperature hydrothermal synthesis in the aqueous solution. This ZnO nanostructure on the cellulose as thin ZnO layer, utilized substrate via simple reaction including the alkaline hydrolysis, was composed by hydrothermal synthesis. It is revealed that growth mechanism of ZnO nano-rod of the ZnO-Cellulose hybrid nanocomposite is governed as the crystal orientation limited by structural and morphological analysis. As the reaction time of chemical process increases, the size of the ZnO nanostructure also increases. These composite materials can be used to smart materials for flexible electronic or electro-mechanical devices such as transistors and strain sensors.

This paper investigates a direct inkjet printing method for electrode patterning on cellulose Electro-Active Paper (EAPap). Flexibility and transparency of the EAPap are advantageous for a versatile substrate in flexible printable electronics. The effects of curing conditions are evaluated by electrical resistivity and morphological analysis. To fabricate EAPap device, inter-digital transducer (IDT) electrodes are printed on the EAPap with drop-on-demand inkjet printing method. Silver patterns are obtained from organometallic silver ink by jetting and heat treatment at 160°C in air. IDT patterns are made on cellulose for variety and extensive application of inkjet printing electronics.

The possibility as a vibration sensor of Electro-Active paper (EAPap) based on piezoelectricity was investigated in the present paper. The EAPap was fabricated by regenerating and tape casting cellulose. The gold, silver and aluminum were deposited on both sides of the cut cellulose film using a thermal evaporator. The sample was coated by thin laminating film for packaging. The simple aluminum cantilevered beam was used for the vibration testing and EAPap was attached on the beam. The original EAPap sensor without grounding and shielding has greatly affected by the surrounding noise such as power noise especially. The power noise reduced dramatically with grounding and shielding of EAPap. The impulsive response of EAPap provided correct dynamic characteristics of the beam. Forced response of EAPap presented that gold and silver electrodes are suitable for EAPap sensor but aluminum electrode provides too many noise due to high resistance. PVDF provided similar characteristics of EAPap, which results EAPap has high potential as a vibration sensor.

As a bio/chemical sensing technique, surface enhanced Raman spectroscopy (SERS) offers sensitivity comparable to that of fluorescence detection while providing highly specific information about the analyte. Although single molecule identification with SERS was demonstrated over a decade ago, today a need exists to develop practical solutions for point-of-sample and point-of-care SERS systems. In recent years, optofluidic SERS has emerged, in which microfluidic functions are integrated to improve the performance of SERS. Advancements in optofluidic SERS are leading towards portable analytical systems, but the devices are currently too expensive and too cumbersome for limited resource settings. Recently, we demonstrated the fabrication of SERS substrates by inkjet printing silver nanostructures onto paper. Using a low-cost commercial inkjet printer, we chemically patterned cellulose paper to form hydrophobic regions, which can control the aqueous sample on the paper microsystem. Additionally, we inkjet-printed silver nanoparticles with micro-scale precision to form SERS-active biosensors. Using these devices, we have been able to achieve detection limits comparable to conventional nanofabricated substrates. Furthermore, we leverage the fluidic properties to enhance the performance of the SERS devices while also enabling unprecedented ease of use. Paper dipsticks concentrate a relatively large sample volume into a small SERS-active detection region at the tip. Likewise, paper swabs collect samples from a large surface area and concentrate the collected molecules into a SERS sensor on the paper. We will summarize the progress in the fabrication and use of these paper-based optofluidic devices, and will describe their use in practical applications for point-of-sample detection.

In this paper, a new data hiding method - writing on wet paper using multi-pixel differencing is presented in order to provide large embedding capacity and improve further steganographic embedding efficiency for the stego-image. It takes into consideration four pixels of a block, and the differences between the lowest gray-value pixel and its surrounding pixels are used to embed the secret data. The receivers can extract secret bits from carrier images only by some matrix multiplications no matter how we embed the secret message. Thus, the invisibility of this steganographic method is achieved in process of secret information transmission. The experimental results show that our scheme has a larger embedding capacity and better robust performance against the methods of active attacks such as noise addition.

This paper contains the case description of reviewing of different research papers for scientific conference and Models related to the chosen case description. The evaluation of the business models is based on the Sequal quality framework. This paper is based on the case description as provided in later sections of this paper; however the case is extended and focused as necessary to explain the business models.

In the present work a non-invasive technological study on three molds from Magnani’s mills in Pescia (Pistoia, Italy) was carried out. The three molds investigated have been those for making: 1) the invitation letters to the marriage between Napoleon and Maria Luisa of Austria in 1810; 2) the paper sheets used by Pablo Picasso in 1917 for the drawings of the Russian Ballets currently preserved in the Picasso Museum in Paris; 3) the holy manuscript Bhagavata Purana realized in India in 1840 and currently preserved in the “Museum of Art” of San Diego. The chemical composition of the metal alloy components were investigated and compared using Laser Induced Plasma Spectroscopy (LIPS), electron microscopy (ESEM-EDX) and Ion Beam Analysis (IBA) while shape and size comparisons were carried out by means of a homemade 3D digital microscopy device. Metallographic characterizations were also carried out on some very small samples. This allowed pointing out the different crafting features of the three molds. The results achieved and represent the first step towards an overall characterization, which will be carried out on Magnani’s mold collections.

Semiconducting ZnO layer chemically grown on regenerated cellulose and its flexible paper transistor were studied. ZnO layer-cellulose composite was prepared by a simple chemical reaction process which included alkaline hydrolysis at low temperature lower than 100 °C and used wet regenerated cellulose as a hydrophilic substrate. By increasing the concentration of ZnO seeding layer on cellulose, the area of ZnO cluster also increases. In the low concentration conditions from 20 mM to 50 mM, it is observed that the average size of ZnO nanorods increases as the seeding concentration increases. However, flower-shaped ZnO structure is observed in higher concentration over 50 mM due to clustering effect during the growth of ZnO rods. Thin ZnO layer composed of nano-rods seemed to be grown well on regenerated cellulose and layer thickness of ZnO was well controlled by reaction time. Structural data of as grown ZnO/cellulose provides the crystal orientation-limited growth mechanism of ZnO nano-rod, which can be controlled by the reaction time of chemical process. Using conventional lift-off process, thin ZnO layer based transistor was fabricated by forming source/drain as well as gate electrode. More detailed ZnO-cellulose based transistor is discussed.

This paper reports a remotely-driven electro-active paper (EAPap) actuator by modulated microwaves. So far we have demonstrated a remotely driven EAPap actuator by means of rectenna and control circuit. The rectenna consists of dipole antenna and rectifying circuit, which converts microwave to dc power. Once microwaves are incident on the dipole rectenna, it converts microwaves into a dc power and the control circuit feeds the power to the EAPap actuator by alternating it so as to produce a bending motion of the EAPap actuator. However, due to the power consumption of the control circuit, the remotely-driven actuator system requires more dc power to activate the control circuit. Thus, we propose a remotely-driven EAPap actuator that does not require the control circuit. Instead of the control circuit, microwaves are modulated with the control signal, and by rectifying the modulated microwaves with the rectenna, the control signal can be regenerated for activating the EAPap actuator. Detailed modulated microwave, rectenna design, fabrication, characterization and the actuation of rectenna-EAPap by modulated microwave are explained.

We report a flexible paper transistor made with regenerated cellulose and covalently bonded single-walled carbon nanotubes. Functionalized single-walled carbon nanotubes (SWNTs) are reacted with N, N-Carbonyldiimidazoles to obtain SWNTs-imidazolides. SWNTs can be covalently bonded to cellulose by acylation of cellulose with SWNTsimidazolides. Using the product, SWNTs covalently bonded cellulose (S/C) composite paper is fabricated and it is mechanically stretched to align SWNTs with cellulose chains. Finally, inter-digital comb shaped source and drain electrode and bottom gate electrode is formed on the paper via lift-off process. Aligned SWNTs can contribute to establishing stable electron channel paths in the cellulose layer. The alignment of SWNTs can be key a role in improving characteristics of the paper transistor. The characteristics of the paper transistor are evaluated by measuring mobility, onoff ratio depending on the alignment of SWNTs in S/C composite paper transistors.

Haptic is one of well-considered device which is suitable for demanding virtual reality applications such as medical equipment, mobile devices, the online marketing and so on. Nowadays, many of concepts for haptic devices have been suggested to meet the demand of industries. Cellulose has received much attention as an emerging smart material, named as electro-active paper (EAPap). The EAPap is attractive for mobile haptic devices due to its unique characteristics in terms of low actuation power, suitability for thin devices and transparency. In this paper, we suggest a new concept of haptic actuator with the use of cellulose EAPap. Its performance is evaluated depending on various actuation conditions. As a result, cellulose electrostatic force actuator shows a large output displacement and fast response, which is suitable for mobile haptic devices.

During his explorations of Africa, David Livingstone kept a diary and wrote letters about his experiences. Near the end of his travels, he ran out of paper and ink and began recording his thoughts on leftover newspaper with ink made from local seeds. These writings suffer from fading, from interference with the printed text and from bleed through of the handwriting on the other side of the paper, making them hard to read. New image processing techniques have been developed to deal with these papers to make Livingstone's handwriting available to the scholars to read. A scan of the David Livingstone's papers was made using a twelve-wavelength, multispectral imaging system. The wavelengths ranged from the ultraviolet to the near infrared. In these wavelengths, the three different types of writing behave differently, making them distinguishable from each other. So far, three methods have been used to recover Livingstone's handwriting. These include pseudocolor (to make the different writings distinguishable), spectral band ratios (to remove text that does not change), and principal components analysis (to separate the different writings). In initial trials, these techniques have been able to lift handwriting off printed text and have suppressed handwriting that has bled through from the other side of the paper.

Recently, there has been a surge of activity in the development of next-generation transparent thin film transistors for use in applications such as electronic paper and flexible organic light emitting diode panels. Amongst the transparent conducting oxides attracting the most interest at present are Amorphous Oxide Semiconductors (AOS) based on ZnO because they exhibit enhanced electron mobility (μ), superior capacity for processability in air and improved thermodynamic stability compared with conventional covalent amorphous semiconductors and existing AOS. Moreover, they give excellent performance when fabricated at relatively low temperature and can readily be made in large area format. Thus, they are projected to resolve the trade-off between processing temperature and device performance and thereby allow fabrication on inexpensive heatsensitive substrates. For the moment, however, an undesireable post-deposition annealing step at a temperature of about 200°C is necessary in order to obtain suitable electrical and optical properties. This paper demonstrates the possibility of directly engineering amorphous ZnO with relatively high conductiviy at room temperature on paper and mylar substrates using pulsed laser deposition.

Lasers can provide a precious tool to conservation process due to their accuracy and the controlled energy they deliver, especially to fragile organic material such as paper. The current study concerns laser modification such as paper cleaning, initially of test papers artificially soiled and then of an original book of the early 20 th Century. The test objects were A4 copier paper, newspaper, and paper Whatman No.1056. During the experiments, ink of a pen, pencil and ink from a stamp was mechanically employed on each paper surface. Laser cleaning was applied using a Q-switched Nd:YAG operating at 532 nm and CO 2 laser at 10.6 μm for various fluences. The experimental results were presented by using optical microscopy. Eventually, laser cleaning of ink was performed to a book of 1934, by choosing the best conditions and parameters from cleaning the test samples, like Nd:YAG laser operating at 532 nm.