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The title compound [systematic name: 2-(benzyloxy)naphthalene], C17H14O, which is used as a sensitiser for thermal paper, has a twisted conformation with a dihedral angle of 48.71 (12)° between the phenyl ring and the naphthyl ring system. In the crystal, one molecule interacts with six neighbouring molecules via intermolecular C—H...π interactions to form a herringbone molecular arrangement.

The flame resistance of kraft paper was greatly modified by an eco-friendly, phosphorus-containing and reactive flame retardant, ammonium phosphite, which was grafted on kraft paper via pad-bake method. The results showed that the limiting oxygen index of treated kraft paper could increase from 19.1 to 48.2%. The results of vertical flammability tests imply that the char length of treated sample decreased from 210 to 45 mm. Thermogravimetry analysis showed that treated kraft paper had the lower initial decomposition temperature and more residues than control sample. Thermogravimetry analysis/infrared spectrometry indicated that the flammable volatile species of treated kraft paper reduced obviously compared with that of control sample. Fourier transform infrared spectroscopy suggested that ammonium phosphite was grafted on the cellulose molecules by P-O-C covalent bonds and the flame retardant is reactive in condensed phase. Scanning electron microscopy showed that the modification had little effect on the surface of kraft paper and the residual carbonized frame of treated kraft paper retained the fiber shape after combustion. EDX results showed that the flame retardant introduced a large amount of phosphorus and nitrogen into kraft paper. X-ray diffraction indicated that the modification did not significantly affect the crystal structure of kraft paper. And the strength of kraft papers slightly declined after the modification, but it still remained well. [ABSTRACT FROM AUTHOR]

"Paper" plays an important role in the development and spread of civilization. However, massive use of paper has led to nonnegligible negative influence on environment. Recently, great progresses have been made in the fields of rewritable paper that has enormous potential in alleviating the increasing demand for paper. Therefore, we report a new photochromic tetraphenylethene-based Schiff base derivative 2-ethoxy-6-(((4-(1,2,2-triphenylvinyl)phenyl)imino)-methyl)phenol (TPENOEt). TPENOEt exhibits reversible photochromic behavior, fast response, simple synthetic step, lower cost and excellent fatigue resistance. The bleaching rate of TPENOEt is tunable by longer wavelength light, white light irradiation and elevated temperature. The fluorescence of TPENOEt is weak in solid state, which increases obviously after grinding with a pestle accompanied by reduced photochromic efficiency and longer response time. These results provide a new view to get insight into the relationship between packing style and fluorescence/photochromism property of Schiff base derivatives. TPENOEt is successfully applied as a visible light driven rewritable paper, 410 nm violet light can serve as a pen, while 420–590 nm visible light and white light is employed as the eraser. The recorded information will be erased in about 15 s after white light irradiation and will be self-erased in 20 min in daylight and in about 15 days in dark. Moreover, TPENOEt can also serve as a UV strength sensor for naked eye detection of UV radiation pollution. Image 1 • TPENOEt exhibits reversible photochromic behavior, fast response, and excellent fatigue resistance. • TPENOEt is successfully applied as a visible light driven rewritable paper. • The recorded information on TPENOEt will be self-erased in 20 min in daylight and in about 15 days in dark. [ABSTRACT FROM AUTHOR]

Innovative and sustainable all-cellulose composites (ACCs) can be obtained by partial dissolution of cellulosic fibers and regeneration of the dissolved fraction. Among cellulose solvents, sodium hydroxide/urea solutions are recognized as promising low-environmental impact systems. In this work, filter paper (FP) was dissolved with a 7 wt% NaOH/12 wt% urea aqueous solution, kept at −18 °C for different time intervals, regenerated with distilled water and finally dried under different conditions. The developed films were characterized in terms of morphology, porosity, optical properties, crystalline structure, hydration and mechanical properties. The porosity of the composites decreased with dissolution time due to the progressive filling of voids as the cellulosic fibers' surface skin layer was dissolved and regenerated. Samples treated for 4 h showed the minimum values of porosity and opacity, high hydration and a substantial change from cellulose I to cellulose II. Hot pressing during drying led to relevant improvements in ACCs stiffness and strength values. [ABSTRACT FROM AUTHOR]

Waste streams generated from pulp and paper mills show high potential to be used as alternatives raw materials for production of clinker. In this context, this work aims to evaluate the use of such materials to obtain hydraulic binders, which are referred to as Ecoclinfeers and Ecocements. Lime mud, wastewater treatment process sludge and biomass ashes were characterized, and five formulations (F1-F5) were developed by applying the Bogue equations. These compositions were processed at three different clinkering temperatures (1350,1440 and 1455 "C). The formulated Ecoclinfeers and a reference hydraulic binder were characterized by X-ray diffractometry to identify the crystalline phases, which were subsequently quantified by the Rietveld method. The results showed that crystalline phase characteristics of clinkers and cements, and compression strengths of ~20 MPa after 28 days curing time were obtained, confirming the potential use of the investigated waste as alternative materials for production of clinker. [ABSTRACT FROM AUTHOR]

Flexible photodetectors functionalized by transition metal dichalcogenides have attracted great attention due to their excellent photo-harvesting efficiency. However, the field of optoelectronics still requires advancement in the production of large-area, broad band and flexible photodetectors. Here we report a flexible, stable, broad band and fast photodetector based on a MoS2/WSe2 heterostructure on ordinary photocopy paper with pencil-drawn graphite electrodes. Ultrathin MoS2/WSe2 nanohybrids have been synthesized by an ultrahigh yield liquid-phase exfoliation technique. The thin sheets of WSe2, and MoS2 contain two to four layers with a highly c-oriented crystalline structure. Subsequently, the photodetector was exploited under ultra-broad spectral range from 400 to 780 nm. The photodetector exhibits excellent figure of merit such as on/off ratio of the order of 103, photoresponsivity of 124 mA W−1 and external quantum efficiency of 23.1%. Encouragingly, rise/decay time of about 0.1/0.3 s was realized, which is better than in previous reports on paper-based devices. [ABSTRACT FROM AUTHOR]

Selecting different metal ions, two novel complexes {[Zn(BCbpy)(m‐BDC)(H2O)] ⋅ 2H2O}n (1) and [Co(H2O)6]0.5[Co0.5(BCbpy)(H2O)2](m‐BDC) ⋅ 3H2O ⋅ DMF (2) have been prepared and structurally characterized in the presence of the viologen ligand 1‐(4‐carboxybenzyl)‐4,4′‐bipyridinium (BCbpy) and 1,3‐benzenedicarboxylic acid (m‐H2BDC). The crystal structures and photochromic properties of two complexes have been investigated in this article. 1 possesses a two‐dimensional (2D) layered structure, while the structure of 2 is zero‐dimensional (0D). As expected, 1 and 2 were discovered to be photochromic accompanying electron transfer (ET). Interestingly, 1 can be dissolved in ethanol solution and deposited on filter paper, applied to a printing medium without ink. [ABSTRACT FROM AUTHOR]

Endo-1,4-β-xylanases belonging to the glycoside hydrolase (GH) 11 family hydrolyze the β-1,4-glycosidic linkages in the xylan backbone to convert polymeric xylan into xylooligosaccharides. GH11 xylanases play an essential role in sugar metabolism and are one of the most widely used enzymes in various industries, such as pulp and paper, food and feed, biorefinery, textile, and pharmaceutical industries. pH is a crucial factor influencing the biochemical properties of GH11 xylanase and its application in bioprocessing. For the optimal pH shifting of GH11 xylanase in industrial applications, various protein engineering studies using directed evolution, rational engineering, and in silico approaches have been adopted. Here, we review the functions, structures, and engineering methods developed for the optimal pH shifting of GH11 xylanases. The various GH11 engineering techniques and key residues involved in pH shifting are discussed based on their crystal and modeled structure. This review provides an overview of recent advancements in the characterization and engineering of GH11 xylanases, providing a guide for future research in this field. [ABSTRACT FROM AUTHOR]

We presented a three-step method for the preparation of superhydrophobic cellulose filter paper. It involved ZnCl 2 pre-treatment to activate the cellulose fibers, a SiO 2 sol-gel process to increase surface roughness and grafting of hexadecyl trimethoxysilane groups to chemically enhance the water repellency. The water contact angle of the modified paper reached 154.8°. XRD analysis confirmed silica as the product from the sol-gel process. EDS and SEM analysis showed that pre-treatment results in greater silica adhesion and retention on the paper surface. The modified paper proved to be self-cleaning and resistant to staining. Further tests under various conditions showed that ZnCl 2 pre-treatment improved the durability of the superhydrophobic paper. It was concluded that pre-treatment of the filter paper prior to superhydrophobic coating results in a disruption in the cellulose crystalline structure that favours greater silica adhesion and retention. Unlabelled Image • ZnCl 2 pre-treatment exposed more -OH groups. • ZnCl 2 -pre-treatment and silica functionalization resulted in strong hydrogen bonding. • ZnCl 2 -pre-treated paper retained more silica. • Operational in various solvent and pH conditions • The paper proved to be self-cleaning, anti-staining and oleophobic. [ABSTRACT FROM AUTHOR]

My comments concern the errors in the crystallographic part of the commented paper. The diffraction patterns are erroneously analysed. The crystal structure was not presented in the commented paper. • Correction of erroneous analysis of diffraction patterns. • Comparison of unit cells relation to the content of Ca dopant. • The crystal structure was not given in the commented paper. [ABSTRACT FROM AUTHOR]

In this paper, far-infrared (FIR) spectroscopic techniques have been employed to detect different calcium carbonate crystal concentrations in powder mixtures. We have compared absorption spectral features of both pure and mixtures of natural ground calcium carbonate (GCC) and synthetic precipitated calcium carbonate (PCC). It is evident that the absorbance data differentiate clearly and unequivocally between calcite and aragonite in the spectral range of 2-18 THz. Also, from the absorbance measurement of two sets of mixtures, we have revealed a linear relationship between the ratio of some selected absorbance peaks of the mixtures and concentration of a particular pigment within the mixture. This innovative technique could be a novel, practicable technique for quality control or for analyzing coating and/or filler pigments and extenders in the paper making and printing industries. Finally, we have proven in the case of paper that, surface roughness and print color play no role as far as the locations and magnitudes of the absorbance spectral features are concerned. [ABSTRACT FROM AUTHOR]

Porous piezoelectric ceramics with an interconnecting pore network (3-3 piezoceramic-air-composites) are a compromising material for sensor applications. Using a biomorphous approach with pre-pyrolysed cellulose fiber paper as template for the impregnation process leads to a novel porous piezoelectric ceramic with a fiber microstructure and benefits on easy shaping of complex structures and high porosity (∼90 vol%). The templates were impregnated by a non-aqueous lead zirconate titanate (PZT) slurry (solid fracture of 52.3%). After residual slurry and binder removal and cellulose/carbon burn-out, sintering was carried out at 1150 °C. Microstructure and composition analyses were done by µCT (“Skyscan 1172”, Bruker), SEM (FESEM, Helios NanoLab 600i FIB Workstation, FEI) and X-ray diffraction measurements (Kristalloflex D500, Siemens AG) evaluation. Geometric density decreased by 30% compared to dense PZT (as reference) a porosity increased from 2.4% up to 86%. The piezoelectric properties as d 33 , relative permittivity and d 31 (measured by “Piezo-Meter PM 300″, Piezo Test) decreased up to 99%. [ABSTRACT FROM AUTHOR]

A sensitive detection method combined with an effective on-line concentration may improve the analytical performance of a paper-based analytical device (PAD), and its merits of low cost and portability in POCT are fully demonstrated. Here, a sensitive PAD system with chemiluminescence (CL) detection and electrokinetic preconcentration was introduced, and the performance was demonstrated by the detection of hemin. A commercially available low cost and miniaturized optical detection module was used for the CL detection. Firstly, hemin was stacked on a simple paper fluidic channel based on field amplified stacking (FAS), and then a CL reagent (luminol–H2O2) was loaded on the stacked band to initiate the CL reaction. The photons were directly detected using the detection module. With optimization of the background electrolyte (BGE), voltage and CL reagent, a limit of detection (LOD) of 0.58 nM for hemin was obtained with a linear range of 1–1000 nM (R2 = 0.995). With FAS, the signal intensity was about 13-fold enhanced. This PAD also exhibited satisfactory selectivity over possible interfering components at a 104 times higher concentration. The applicability of the PAD was demonstrated by the detection of hemin from iron supplements and human serum samples. With total manual operation, recovery rates of 84.8–115.6% were obtained with an RSD of less than 14.3%. With the introduction of the optical detection model, and together with FAS, both the LOD and dynamic range of this PAD were effectively improved. [ABSTRACT FROM AUTHOR]

Abstract A new method was employed to synthesize a novel high voidage ZIF-8 membrane over paper-like stainless steel fibers (PSSF). Firstly, paper-like stainless steel fibers (PSSF) were prepared by wet lay-up papermaking and sintering process, then the ZIF-8 membrane was coated on the PSSF support by secondary growth process. The effects of the seed layer growth time, the Hmim (2-methylimidazole)/Zn (Zinc nitrate hexahydrate) molar ratios, the solvothermal synthesis temperature and time on properties of ZIF-8 membrane/PSSF composites were investigated by modern characterization methods. The experimental results indicated that the void volume of ZIF-8 membrane/PSSF composites reached 89%. The optimal specific surface area of composites was 398 m2/g and the total pore volume was 0.174 cm3/g. Specifically, the size of seeds were approximately 250 nm when Hmim/Zn molar ratios and seed layer deposition time were 80 and 12 h, respectively. Under the condition of optimal seed layer, ZIF-8 membrane/PSSF composites showed outstanding continuity, compactness, free-defect and crystal shape when solvothermal synthesis time and solvothermal synthesis temperature were 24 h and 100 °C, respectively. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

We developed paper-based powder X-ray diffraction (PP-XRD) to implement phase identification and/or crystal structure determination on paper-based platforms. These aims are not possible with other paper-based detectors, such as Raman spectroscopy and mass spectrometry. PP-XRD overcomes these limitations. Here we reported the simple and low-cost in situ PP-XRD protocol for phase identifications of inorganic and organic materials. We demonstrated that sample amounts of lead nitrate on paper substrate can be reduced into 1/30 of conventional ones by using the standard glass substrate at the same signal-to-noise ratio (S/N) of the X-ray diffraction (XRD) pattern. The paper-based method was comparable in sample quantity and intensity with zero background holder method, even though single crystal Si(100) substrate as zero background holder was used for the specimen preparation of CTAB (C 19 H 42 BrN). More importantly, paper substrates helped reduce preferred orientation that was generally present in routine powder XRD. Also, combined with paper chromatography, overlap peaks were eliminated in the XRD detection patterns of lead nitrate and cobalt nitrate hexahydrate. This new PP-XRD protocol may accelerate the process to identify phase or determine the molecular structures of new materials using trace sample directly. It also includes a hyphenated technique of powder XRD with a simple paper-based microfluidic separation of chemical solutions. [ABSTRACT FROM AUTHOR]

Mg-Al-CO3 LDH was synthetized, using co-precipitation, and was used in flame-retardant paper as filler. The crystallizations, granularities of Mg-Al LDH, and characters of flame-retardant papers were investigated through XRD, FT-IR, TEM, TG-DTA, and SEM techniques. The results indicated that Mg-Al hydrotalcites were layered hexagonal nanoparticles, with high positive charge density, perfectly crystallized structure, and striking performance in furnish retention improvement. Mg-Al hydrotalcites with high whiteness can improve the whiteness of flame-retardant paper; the whiteness of flame-retardant paper increased by 82.1% while the dosage of LDH was 20wt%, but the Mg-Al hydrotalcites affected the strength index of flame-retardant paper adversely. The flame-retardant papers based on fiber using Mg-Al hydrotalcites as fillers showed excellent inflaming retarding performance. The oxygen index of the flame-retardant paper produced was above 25% at the dosage of 20wt%. [ABSTRACT FROM AUTHOR]

The successful attempt to solve the crystal structure of Co(CO3)0.5(OH)·0.11H2O (denoted CCH), based on synchrotron powder diffraction data, leads to a drastic revision of the chemical formula to Co6(CO3)2(OH)8·H2O [hexacobalt(II) bis(carbonate) octahydroxide monohydrate] and to a hexagonal cell instead of the orthorhombic cell suggested previously [Porta et al. (1992). J. Chem. Soc. Faraday Trans.88, 311–319]. This results in a new structure‐type related to malachite involving infinite chains of [CoO6] octahedra sharing edges along a short c axis, delimiting tunnels having a three‐branched star section. All reports discussing cobalt hydroxycarbonates (CCH) without any structural knowledge and especially its topotactic decomposition into Co3O4 have, as a result, to be reconsidered. The crystal structure of Co6(CO3)2(OH)8·H2O was solved ab initio and refined from synchrotron powder diffraction data. [ABSTRACT FROM AUTHOR]

The crystal structure of a new bisphenol S derivative, 3,3′-diallyl-4,4′-dihydroxydiphenyl sulfone was analyzed. This compound is used as colour developer in high-performance thermal paper, because of its high colour sensitivity and excellent image stability. In the crystalline phase, each molecule of this derivative is linked to four neighbouring molecules by O H⋯O S intermolecular hydrogen bonds. In order to understand the solid-state properties of the new derivative, its hydrogen bonding features were compared to those of the parent bisphenol S compound. The hydrogen bonding network of the new derivative forms two-dimensional square lattice sheets stacked along the b axis. This stacking arrangement, which is different from that of the unsubstituted compound, results in a lower number of hydrogen bonds per unit volume. This structural feature was considered to be correlated with the considerably lower melting point of the new derivative compared to that of the unsubstituted one. This property would result in a good coloration sensitivity of the new derivative when used as colour developer. [ABSTRACT FROM AUTHOR]

My comments concern the significant errors in the crystallographic part of the commented paper. The diffraction patterns are erroneously analysed. It is supposed that the correct crystal structure is an Aurivillius phase Bi 5 Ti 3 FeO 15 with m = 4. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the feasibility of using insoluble dietary fiber (IDF) from Chinese cabbage to make a novel edible paper. The structural, physical, and chemical properties and crystallinity of the IDF were first analyzed. The characteristics and fracture surfaces of the handsheets made by the IDF were then studied. The paper performance was finally measured. We found four types of fiber morphology in IDF after the original Chinese cabbage fiber was treated with 8 wt% alkali solution. The IDF-based paper showed a smooth surface, soft and transparent texture, and good strength. The IDF effectively enhanced the paper-packaging performances when it was mixed with wood fiber, although the performance of the IDF-based paper was lower than that of the wood pulp-based paper. The IDF is edible and suitable for direct contact with foods or drugs. Therefore, the IDF-based edible paper has significant development potential for food and pharmaceutical packaging in the future. [ABSTRACT FROM AUTHOR]

Pectinases are upcoming enzymes in the biotechnological sector. This large group of enzymes involves in break down of pectic polysaccharides, the major component of middle lamella in plant cell wall. The pectin degrading enzymes are categorized according to their mode of action and release of degradative products. Various filamentous fungi, yeast, and bacteria are the common sources of microbial pectinases. Solid state fermentation is more preferable for extracellular microbial pectinases production over the submerged fermentation. A group of genes regulates the expression of pectinolytic enzymes. Mostly, all the enzymes share a common parallel ? helix topology which consists of a single domain of parallel β-strands folded into a large right-handed cylinder. These enzymes are ecofriendly tools for industrial applications and being used in various sectors like wine, food, paper industry, waste paper recycling, fruit juice preparation, processing of tea-coffee, animal feed preparation. [ABSTRACT FROM AUTHOR]

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