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Significance: It is commonly assumed that using the objective lens to create a tightly focused light spot for illumination provides a twofold resolution improvement over the Rayleigh resolution limit and that resolution improvement is independent of object properties. Nevertheless, such an assumption has not been carefully examined. We examine this assumption by analyzing the performance of two super-resolution methods, known as image scanning microscopy (ISM) and illumination-enhanced sparsity (IES). Aim: We aim to identify the fundamental differences between the two methods, and to provide examples that help researchers determine which method to utilize for different imaging conditions. Approach: We input the same image datasets into the two methods and analyze their restorations. In numerical simulations, we design objects of distinct brightness and sparsity levels for imaging. We use biological imaging experiments to verify the simulation results. Results: The resolution of IES often exceeds twice the Rayleigh resolution limit when imaging sparse objects. A decrease in object sparsity negatively affects the resolution improvement in both methods. Conclusions: The IES method is superior for imaging sparse objects with its main features being bright and small against a dark, large background. For objects that are largely bright with small dark features, the ISM method is favorable.

Whiteness is one of the most important characteristics of a printing paper. There is a stable relationship between the printed and optical properties of the paper. At the same time, the understanding of whiteness in the papermaking and printing industries is significantly different. Such miscommunication negatively affects the quality of printed products, since the choice of a suitable paper (or cardboard) is difficult to a certain extent. One of the ways to get out of this situation is to create a simple and clear computational model of the white paper, which would not depend on any physical standards. The model would help when conducting the input control in printing plants and would allow one to establish communication between industries. This work is devoted to the description of such a model. © 2020 American Institute of Physics Inc.. All rights reserved.

The integration of smart IT devices and biochemical assays with optical biosensing technology facilitates the development of efficacious optical biosensors for many practical diagnostic fields, owing to their minimized use of high-technical electronic components and simple operation. Herein, we introduced a simple optical biosensing system based on the specific wavelength filtering principle and count-based analysis method. The developed system uses a smartphone with a paper-based signal guide and a biosensing channel. The paper-based signal guide was prepared by printing red patterns of various brightness on a black background. Given that a blue product is generated as a result of horseradish peroxidase (HRP)-based enzymatic reaction in the biosensing channel, the channel could be used as a blue filter that absorbs red light. When red light reflected from the red pattern is absorbed by the channel, the pattern appears black. As such, the color of the patterns is assimilated with the black background, so it seems to disappear. Consequently, the amount of blue product relative to the concentration of the target analyte can be measured by counting the number of observed patterns on the paper-based signal guide. In this study, the concentration of urinary C-telopeptide fragment of type II collagen (uCTX-II, 0–10 ng/mL) was measured using the developed system without complicated equipment. In addition, the quantitative analysis of uCTX-II in the real urine sample was successfully performed. Therefore, we expect that the developed optical transducing system could be practically used for point-of-care testing (POCT) diagnosis under resource-limited environmental conditions.

Fluorescent test papers are promising for the wide applications in the assays of diagnosis, environments and foods, but unlike classical dye-absorption-based pH test paper, they are usually limited in the qualitative yes/no type of detection by fluorescent brightness, and the colorimetry-based quantification remains a challenging task. Here, we report a single dual-emissive nanofluorophore probe to achieve the consecutive color variations from blue to red for the quantification of blood glucose on its as-prepared test papers. Red quantum dots were embedded into silica nanoparticles as a stable internal standard emission, and blue carbon dots (CDs) were further covalently linked onto the surface of silica, in which the ratiometric fluorescence intensity of blue to red is controlled at 5:1. While the oxidation of glucose induced the formation of Fe(3+) ions, the blue emission of CDs was thus quenched by the electron transfer from CDs to Fe(3+), displaying a serial of consecutive color variations from blue to red with the dosage of glucose. The high-quality test papers printed by the probe ink exhibited a dosage-sensitive allochromatic capability with the clear differentiations of ~5, 7, 9, 11mM glucose in human serum (normal: 3-8mM). The blood glucose determined by the test paper was almost in accordance with that measured by a standard glucometer. The method reported here opens a window to the wide applications of fluorescent test paper in biological assays.

Optical characteristics of papers significantly affect the quality of printed products, and they vary depending on the raw materials and the method of production used, so that the features of the material of the same grade, issued by different enterprises, have significant differences. Modern production methods of rapid control of the optical characteristics of papers do not exist. We investigate the relationship between the optical characteristics of printing papers and their elemental composition in order to use the data obtained to create such a method. Spectrophotometric measurements and X-ray fluorescence analysis of 254 samples of printing paper and paperboard, as well as cellulose, were carried out. It is proposed to use the CIE Lab color coordinates as a quantitative estimate of the optical characteristics of papers. The relationship between the content of certain chemical elements and the optical characteristics of the paper is established. Clustering of papers on their optical characteristics and elemental composition was carried out. There are 3 explicit clusters have been found. Оптические характеристики бумаг существенно влияют на качество полиграфической продукции, при этом они изменяются в зависимости от используемого сырья и способа производства, так что характеристики материала одного и того же сорта, выпущенного разными предприятиями, имеют существенные различия. Современных производственных методов быстрого контроля оптических характеристик бумаг не существует. Мы исследуем связь оптических характеристик полиграфических бумаг и их элементного состава для того, чтобы использовать полученные данные для создания такого метода. Проводились спектрофотометрические измерения и рентгено-флуоресцентный анализ 254 образцов полиграфических бумаг и картонов, а также целлюлозы. Предложено в качестве количественной оценки оптических характеристик бумаг использовать CIE Lab координаты цвета. Установлена связь содержания определенных химических элементов и оптических характеристик бумаги. Проведена кластеризация бумаг по их оптическим характеристикам и элементному составу. Обнаружены 3 явных кластера.

Background:Paper is one of the important inputs for the printing industry, and the most important leading parameter in the printing process is its brightness. Brightness can be brought to paper using coatings and sizing. Desired surface properties and, most importantly, surface roughness can be achieved by changing the contents of the coating and sizing of the materials it contains. The use of biomaterials is becoming more important in the paper industry, as they represent substances with a lower carbon footprint. Fish scales are already used as a filling material, cosmetic material and fish food, as well as for determining the age of fish.Methods:Fish scales were brought to different sizes by a milling process. Paper formulations including different amounts of fish scales were prepared with fish scales, and coatings on raw paper were subjected to test printings in IGT-C1, with formulations and physical characteristics of coatings such as brightness, lightfastness, strength, adhesion etc. being determined.Results:Regarding the value of yellowness, mixtures of 2.5%-10% can be used. The maximum value of brightness was obtained from a mixture of 10%. Aging visibly changed the colors.Conclusions:The coatings obtained were brighter than the initial coating compositions. The top quality formulation was the coating with 5% medium-sized fish scale particles.

msufbd Kâğıt, çizim, baskı veya ambalaj amacıyla kullanılan ince malzemedir. Genel olarak ağaç liflerinden elde edilen selüloz hamurunun preslenmesiyle oluşturulan levhaların kurutulması sonucunda elde edilir. Günümüzde kâğıt, basım ve ambalaj sektörünün en önemli malzemesidir. Teknolojik gelişmeler, reklam sektörünün gelişimi ve bunun sonucunda tüketici beklentilerinin artmasıyla kâğıttan da beklentiler artmıştır. Bu yüzden kâğıda birtakım özellikler kazandırmak için kaplama işlemi yapılır. Bu işlemin temel amacı, ham kâğıdın üzerine pigment, bağlayıcı ve bazı katkı maddelerinden oluşan ince bir film tabakasını kaplayarak kâğıt liflerinin üzerini örtmek, aralardaki boşlukları doldurmak ve bu sayede daha düzgün bir yüzey elde etmektir. Basım sektörü için kâğıdın basılabilirlik parametrelerinin iyi olması gerekmektedir. Bu parametreleri genel olarak yüzeyin düzgünlüğü, pürüzsüzlüğü, parlaklığı, opaklığı ve beyazlığı olarak sayabiliriz. Kâğıt üzerine yapılan kaplamalar için yaygın olarak kullanılan pigmentler kaolin, kalsiyum karbonat, titanyum dioksit ve bağlayıcı olarak ta polivinil alkol türleri, nişasta ve lateks maddeleri sayabiliriz. Basım tekniklerindeki gelişmeler, mürekkebin yapısı ve transfer şekli farklı fiziksel özelliklerde kağıtları kullanmayı gerektirmektedir. Yapılan çalışmada iki farklı bağlayıcı ile tek bir pigment kullanılarak kaplama formülasyonu hazırlanmış ve ham kâğıt üzerine kaplanmıştır. Bağlayıcının kâğıdın fiziksel özelliklerine etkisi incelenmiş ve yorumlar yapılmıştır. Bağlayıcı olarak polivinil alkol kullanılan kaplamanın parlaklık değeri daha yüksek çıkarken, bağlayıcısı nişasta olan kaplamanın ise opaklığı daha yüksek elde edilmektedir. Ayrıca kaplanmış kağıtların kalenderleme işlemleri de yapılarak kalender işlemi sonrasındaki değişimler de paylaşılmıştır. Paper is a thin material used for drawing, printing or packaging. Generally, it is obtained as a result of pressing the cellulose pulp obtained from the wood fibers. Paper is the most important material in printing and packaging material. Nowadays, as a result of technological developments and the growth of the advertising industry, the expectations from the paper have increased. For this reason, paper coating process is done for having some physical properties. The main purpose of paper coating process is to cover the paper fibers by filling a thin film layer of pigment, binder and some additives onto the base paper or cardboard, to fill in the gaps between them and to obtain a smoother surface. Paper has to have better printability parameters in the printing industry. We can explain these parameters as surface smoothness, roughness, brightness, opacity and whiteness. Most commonly pigments used in paper coating are kaolin, clay and titanium dioxide and on the other hand binders are latex, starch and polyvinyl alcohol types. It requires using paper having different physical properties because of development in printing techniques, ink type and ink transfer method. In this study, the coating formulations were prepared using a pigment and two binders and coated on the base paper. The effect of the binder on the physical properties of the paper was examined and commented on. Coating used polyvinyl alcohol as a binder has a higher brightness value, whereas coating with starch has a higher opacity. Also, the coated papers were calendered and changing of physical properties after calendering process is shared. 322353

7 páginas, 6 figuras, 4 tablas -- PAGS nros. 181-187, High-quality flax pulp was bleached in a short totally-chlorine-free (TCF) sequence. The LP biobleaching sequence includes an enzyme treatment with laccase in the presence of HBT as mediator (L stage) and a hydrogen peroxide stage (P stage). The operating conditions for the laccase HBT system were optimized by using a sequential statistical plan involving four variables, the influence of which on the properties of the pulp after the P stage was examined over enclosed operation conditions regarding a future industrial application. Mathematical models accurately predicting both pulp properties in terms of the previous four variables. This biobleaching sequence allows obtaining an increase in ISO brightness of 40% and a delignification of 80%. Process variables optimization in flax pulp biobleaching allows establishing the application conditions most appropriated to obtain certain pulp properties and that turn out to be easily adaptable to existing industrial processes. As a novelty, toxicity measurements were determined in L stage effluents. The results of toxicity show that it is possible to apply this LP sequence without having a negative environmental impact

Wood shortages, environmental pollution and high energy consumption remain major obstacles hindering the development of today’s pulp and paper industry. Energy-saving and environmental friendly pulping processes are still needed, especially for non-woody materials. In this study, soda-oxygen pulping of bagasse was investigated and a successful soda-oxygen pulping process for bagasse at 100 °C was established. The pulping parameters of choice were under active alkali charge of 23%, maximum cooking temperature 100 °C, time hold at maximum temperature 180 min, initial pressure of oxygen 0.6 MPa, MgSO4 charge 0.5%, and de-pithed bagasse consistency 12%. Properties of the resultant pulp were screened yield 60.9%, Kappa number 14, viscosity 766 dm3/kg, and brightness 63.7% ISO. Similar pulps were also obtained at 110 °C or 105 °C with a cooking time of 90 min. Compared with pulps obtained at higher temperatures (115–125 °C), this pulp had higher screened yield, brightness, and acceptable viscosity, while the delignification degree was moderate. These results indicated that soda-oxygen pulping at 100 °C, the lowest cooking temperature reported so far for soda-oxygen pulping, is a suitable process for making chemical pulp from bagasse. Pulping at lower temperature and using oxygen make it an environmental friendly and energy-saving pulping process.

Background: The operative image for minimal access surgery currently is displayed on a monitor located outside the sterile field. It is ergonomically advantageous to locate the image adjacent to the surgeon’s hands by projection onto a sterile screen, but there has been no research into the optimal screen material. Methods: Several screen materials were compared for image resolution, brightness, variation of brightness with viewing angle, and image artifact. Results: Glossy materials perform poorly, whereas finely grained surfaces improve image clarity. Excessive roughness and incomplete opacity limit the image resolution. Conventional screen fabrics are unsuitable in this application. Ambient lighting and projector brightness affect image contrast, but a correct choice of material can address this. Practical issues such as moisture absorbency and ease of sterilization are considered. Conclusions: Potential screen materials were rejected because of excessive glare, poor resolution, and image artifact. Finely textured surfaces (e.g., polystyrene sheeting) provide an acceptable screen.

The image processing and analysis is interesting non destructive method for determining the number of the residual dirt specks within the defined size classes and the area they occupy in handsheets produced from fibers in different phases of the prints recycling process or produced on the paper. Dirt speck include the ink particles in the deinked pulp. The justification of the image analysis application of handsheet made from the fibers during the different paper recycling phases in dependence to the technique which was used in printing. In results interpretation, the measuring results of the relevant optical factors of the recycled fibers were used and discussed in relation to the division of the size and number of particles obtainer by image analysis. A comparison between the two image analysis software tools is given. Statistical techniques such as factorial design and analysis of variance (ANOVA) were used to interpret the findings.

A central composite factor design was used to examine the influence of independent variables in the acetone pulping of wheat straw (processing temperature, time, and acetone concentration) on the yield of the resulting pulp, and on various physical properties of paper sheets (breaking length, stretch, burst index, tear index and brightness) obtained from it. Equations that related each dependent variable to the different independent variables were obtained, and these reproduced the experimental results for the yield, breaking, stretch, burst index and brightness obtained at temperatures, times, and acetone concentrations over the ranges 140–180°C, 60–120 min and 40–80%, respectively, with errors less than 20%. Obtaining the optimum breaking length, stretch, burst index and tear index for the paper sheets (3456 m, 1.42%, 1.36 kN/g and 3.86 mNm 2 /g, respectively) entails using a high temperature; the processing time and acetone concentration only influence stretch, optimization of which requires using a short time and a low concentration. The optimum brightness (30.44%) is achieved with a low temperature, a short time and a medium acetone concentration. In order to minimize losses of solvent during its recovery and recycling while ensuring acceptable levels of the properties of the paper sheets, a high temperature, a low acetone concentration and a short time can be used; the brightness level thus obtained is only 10% lower than the optimum value.