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Members of the IQ Consortium ″Working Group on Characterization on Amorphous Solid Dispersions″ shares here a perspective on the analytical challenges, and limitations of detecting low levels of crystalline drug substance in amorphous solid dispersions (ASDs) and associated drug products. These companies aim to employ highly sensitive commercially available analytical technologies to guide development, support control strategies, and enable registration of quality products. We hope to promote consistency in development and registration approaches and guide the industry in development of "characterization best practices" in the interest of providing high quality products for patients. The first half of this perspective highlights the unique challenges of analytical methodologies to monitor crystalline drug substance in ASDs and their associated drug products. Challenges around use of limit tests, analyte spiking experiments, and method robustness are also underscored. The latter half describes the merits and limitations of the diverse analytical "toolbox" (such as XRPD, NIR and DSC), which can be readily applied during development and, in some cases, considered for potential application and validation in the commercial QC setting when necessary.

In order to minimize environmental impact zeolite A was synthesized using waste from the paper industry. This waste is composed of cellulose, kaolin and calcium carbonate. Waste purification was carried through thermal and chemical treatment, which consisted of initial calcination, acid washing with HCl, then calcination of the solid fraction to obtain metakaolin and evaporation of the liquid fraction to obtain CaCl2. Zeolite 4A was produced by static autoclaving under hydrothermal synthesis at different temperatures, crystallization times and NaOH concentrations. As a source of aluminum and silicon metakaolin was used. The synthesis of zeolite 5A was performed by ion exchange with CaCl2. After that, the waste paper (in natura and HCl treatment) and the zeolites 4A and 5A were characterized by XDR, SEM, FTIR, AAS and thermal analysis. The temperature is a key factor in zeolite synthesis at lower concentrations allowing one to obtain zeolite 5A by ion exchange with zeolite 4A.

We have previously reported that crystalline samples of 1-acetylaminopyrene (AAPy), 1-octanoylaminopyrene (OAPy), and 1-stearoylaminopyrene (SAPy) exhibited mechanochromic luminescence. In the present study, we have found that these 1-alkanoylaminopyrenes adsorbed onto cellulose papers also exhibited mechanochromic luminescence; however, their behaviors were essentially different from those observed for their crystalline samples. In addition, these cellulose papers were found to exhibit reversible emission color change upon alternate exposure to ethanol and water vapors. It was suggested that 1-alkanoylaminopyrene molecules were dispersed in the paper without aggregation or crystallization and that intermolecular distance of 1-alkanoylaminopyrenes in the paper was reduced by either mechanical stress or exposure to ethanol vapor, resulting in increasing the sites where excimers could be formed and/or in enhancing the efficiencies of energy migration to reach the excimer sites.

Wt% of aragonite, a CaCO(3) polymorph, increased with higher hydraulic activity ( degrees C) of limestone in precipitated calcium carbonate (PCC) from the lime-soda process (Ca(OH)(2)-NaOH-Na(2)CO(3)). Only calcite, the most stable polymorph, was crystallized at hydraulic activity under 10 degrees C, whereas aragonite also started to crystallize over 10 degrees C. The crystallization of PCC is more dependent on the hydraulic activity of limestone than CaO content, a factor commonly used to classify limestone ores according to quality. The results could be effectively applied to the determination of polymorphs in synthetic PCC for eco-friendly paper manufacture.

Solid-state shear pulverization (SSSP) is a continuous process that overcomes challenges in producing well-dispersed polymer composites that cannot be made by twin-screw melt extrusion. We use SSSP to produce 85/15 wt% polypropylene/waste paper biocomposites with polypropylene pellets and 2-cm-square waste paper pieces as starting material. Single-pass SSSP achieves effective filler size reduction and dispersion within the polypropylene matrix. We determine how waste paper size reduction and composite properties are functions of specific energy input and tune specific energy input by SSSP screw design and throughput. Composites made at moderate to high specific energy input (14–35 kJ/g) have 25 to nearly 50% of filler particles at sub-micron size; relative to neat polypropylene, composites exhibit a 70% increase in Young’s modulus, retention of neat polypropylene yield strength, and a ∼50% reduction in crystallization half-time. Estimates indicate that the cost of such biocomposite materials made by SSSP is less than that of virgin polypropylene.

Polyhydroxybutyrate (PHB) is a hydrophobic, biodegradable biopolymer, which can be a potential substitute for currently used synthesized polymers in the packaging in- dustry. However, its utility is often limited by its brittleness and poor mechanical properties, mainly because of its through- thickness fractures. In this study, we laminate and crystallize PHB on glassine paper by hot-pressing and tune the crystal- lization conditions to minimize cracking. Glassine paper is im- permeable to PHB granules and allows the formation of a distinguishable bilayer of PHB. It was found that glassine paper serves as a soft substrate, which increases the number of nu- cleation sites of the spherulites and prevents growth of the cracks in the neighboring PHB layer. Quenching the films to the crystallization temperature was found to minimize cracking enough to reduce the water vapor transmission rate to 15- 25 gm � 2 day � 1 , irrespective of the crystallization temperature; however, the mechanical properties improved only at the crys- tallization temperatures below 77 C, perhaps due to the local stress in the existing cracks at higher crystallization tem- peratures. The optimum crystallization conditions were found to be quenching the film in an ice bath and crystallization at room temperature, by which we obtained mechanical strength and Young's modulus of 80 MPa and 2:5 GPa, respectively, and a water vapor transmission rate of 20 g m � 2 day � 1 . Our results suggest a simple and cost-effective method to produce PHB films with enhanced mechanical and barrier properties.

This study corresponds to a PhD thesis with financial of the Ministry of Research. The objectiveof this work is to elaborate a based-paper titanium/silica photocatalysis for on stream flue gasdepollution (volatile organic compounds) stemming from processes of printing. The volatileorganic compound used in this study is the Ethanol. Particles of hollow silica were synthesizedand used as a support for nano particles of titanium dioxide, which were elaborated by sol-gelmethod. A continuous reactor was designed and used to treat the polluted gaseous flow. Theethanol passes through the photocatalytic paper irradiated by a UV lamp. Several photocatalyticspapers were elaborated and characterized by several techniques (MEB, Spectroscopy Raman,DRX).A modeling of the reactor and the support (photocatalytic paper) was developed and proposed.This modeling integrates the Langmuir – Hinshelwood kinetic and the variation of the intensitywith position in layer’s paper using the Kublka-Munk model., Les travaux présentés s’inscrivent dans le cadre d’une thèse financée par le ministère de la recherche. L’objectif du travail est d’élaborer un papier contenant un charge composite(TiO2/SiO2) photocatalytique permettant d’éliminer des composés volatils organiques issus des procédés d’imprimerie. Le composé organique volatil ciblé lors de ce travail de recherche est l’éthanol. Des particules de silice creuse ont été synthétisées et utilisées comme support pour desnano particules d’oxyde de titane élaborées par méthode sol-gel. Un réacteur continu a été conçuet utilisé pour traiter le flux gazeux pollué. Le gaz à traiter passe à travers le papierphotocatalytique irradié sous UV. Plusieurs supports ont été fabriqués et caractérisés parplusieurs techniques (MEB, Spectroscopie Raman, DRX). L’étude photocatalytique a permisd’optimiser la composition de ces supports. Une modélisation du réacteur et du support (papierphotocatalytique) a été développée et proposée. Cette modélisation intègre la cinétiquephotocatalytique (de type Langmuir–Hinshelwood), la diffusion de la lumière au sein du papiersuivant le modèle de Kublka-Munk et l’hydrodynamique du réacteur.

Paper sludge ash (PSA) was partially converted into zeolites by reaction with 3 M NaOH solution at 90°C for 24 h. The PSA had a low abundance of Si and significant Ca content, due to the presence of calcite that was used as paper filler. Diatomite, which contains amorphous silica and dissolves easily in alkali solution, was mixed with the ash, and then added to the NaOH solution to increase its Si content during alkali reaction and thus synthesize zeolites with high cation exchange capacity (CEC). The original ash without addition of diatomite yielded hydroxysodalite with CEC ca. 0.5 mmol/g. Addition of diatomite to the ash yielded zeolite-P with a higher CEC (ca. 1 mmol/g). The observed concentrations of Si and Al in the solution during the reaction explain the crystallization of these two phases. The reaction products were tested for their adsorption capacity for nutrients from liquid fertilizer, such as K+, NH4+ and PO43−. The product with zeolite-P exhibits high ability to adsorb these nutrients from liquid fertilizer, which is desirable for application in soil improvement.

Glass-ceramics were prepared from mixtures of wastes generated from refining of silica sand and kaolin clay (Kira) and paper sludge ash. Kira and paper sludge ash were mixed in mass ratios of 55/45. The mixtures were melted at 1400 °C and quenched in water to obtain glasses. The quenched glasses were ground to

This paper addresses the question of whether or not there are fundamental differences in the composition of magmatic-hydrothermal fluids in barren versus variably mineralized systems, and if so, at which stage of magmatic-hydrothermal evolution the differences were generated. Combining microthermometry and laser ablation ICP-MS, we studied high-temperature, premineralization fluid inclusions in three barren granites, one Sn-W–mineralized granite, one porphyry Cu-mineralized intrusion, one porphyry Mo-mineralized intrusion, and one Th-U-REE–mineralized granite, and compared the results with published data from 10 other intrusive systems. Many of the fluid inclusions are paragenetically associated with melt inclusions, providing direct insights into the stage at which metals were transferred from the crystallizing magma into the exsolving aqueous fluids. In 10 out of 14 magma systems in which the physical and compositional properties of the magmatic fluid(s) could be determined, the exsolved aqueous fluid was a single phase of relatively low salinity (2–13 wt % NaCl equiv; avg 5 wt % NaCl equiv), confirming predictions based on indirect evidence and observations made in earlier studies. Furthermore, in magmas that crystallized at low pressure ( 1.3 kbars) the opposite behavior occurred, as predicted by published numerical models of aqueous fluid-saturated magma crystallization. During the transition from magmatic to subsolidus conditions, both pressure and temperature within and adjacent to intrusions decreased, leading to widespread vapor-brine immiscibility. Due to the low salinity of the single-phase parent fluid the two-phase field generally was entered from the vapor side, resulting in condensation of subordinate amounts of brine from the low-density bulk fluid. If the transition from single- to two-phase aqueous fluid occurred in locally closed systems one can use the compositions of vapor and brine in subsolidus boiling assemblages to calculate the composition of the bulk fluid. This method was applied to those occurrences in which no single-phase parent fluid was found (i.e., where the earliest aqueous fluid found was already in the two-phase field). The metal content of the least fractionated low-salinity fluids at each location correlates positively with the type and amount of mineralization in the associated intrusions, with high Cu concentrations being observed in fluid related to porphyry Cu deposits, high Sn and W concentrations in fluids related to Sn-W mineralization and high Ce concentrations in fluids related to REE mineralization. The earliest fluids in barren intrusions are comparatively metal poor, except for two cases in which certain metal concentrations are as high as in mineralized systems. A significant portion of the geochemical signature of barren versus mineralized intrusions was thus inherited from earlier stages in the development of these magma systems. In the case of Mo, Sn, W, and Ce, the correlation between fluid composition and type and amount of mineralization is more distinct in high-temperature brines than in the least fractionated low-salinity fluids. This, together with other lines of evidence, suggests that brine condensates play a central role in the formation of Sn, W, Mo, and REE deposits. In the case of porphyry Cu (-Au) systems it appears more likely that the greater proportion of metal precipitated from the vapor phase, although brines may have played a significant role as well.

The effect of heat treatment on the structure, piezoelectricity and actuation behavior of cellulose electroactive-paper actuators was studied by infrared spectroscopy, piezoelectricity measurement and the tip displacement test. After heat treatment at 60 °C for 2 h, the piezoelectric coefficient ( d 31 ) was enhanced nearly 10-fold as compared to that of non-heat-treated films. However, when the treatment temperature was raised above 60 °C the piezoelectric coefficients were higher than the non-treated film but lower than that of film treated at 60 °C. Infrared and UV–visible spectroscopy suggested that there were changes in chemical structure at higher treatment temperatures. Furthermore, the tip displacement tests performed on the actuators also showed almost same trend as that of the piezoelectric constant.

Dissolution kinetics of struvite are important for optimizing intentional struvite crystallization, as well as for ensuring the efficient use of the crystallized products. Dissolution experiments were carried out for struvite pellets grown in a pilot-scale fluidized bed reactor. To determine the kinetics and mechanism of the dissolution process in a batch reactor system, two different theoretical models were tested. The experimental values were found to fit well with both models. In a mixed flow-through reactor system, the constituents release became stoichiometric when the input solution had an alkaline pH. The dissolution rates for struvite pellets were found to decrease with increasing pH due to proton promoted dissolution. After a transition from around 7.5 to 8, the rate of dissolution increased with the increase in pH, because of the hydroxyl promoted dissolution.

An improved antibody-coated sensor system based on quartz crystal microbalance analysis on Salmonella spp. was developed making use of thiolated antibody immobilization onto one gold electrode of the piezoelectric quartz crystal surface. The best results in sensitivity and stability were obtained with the thin layer of a thiol-cleavable, heterobifunctional cross-linker, sulfosuccinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate (sulfo-LC-SPDP). The long bridge of this reagent could function as a spacer, facilitating antibody-Salmonella interaction on the gold electrode. After the addition of a S. typhimurium suspension into a reaction cell with 0.1 M sodium phosphate buffer, pH 7.2, the resonant frequency decreased conspicuously. The time required for maximum frequency shift was about 30-90 min. Sensor response was observed for the microbial suspensions ranging from 9.9 x 10(5) to 1.8 x 10(8) CFU/ml.

Crystallization of mold fluxes for low carbon (LC) and medium carbon (MC) steels has been observed in-situ on cooling from molten state by using a confocal laser scanning microscope with an infrared image furnace. Primary crystallization of cuspidine is found to take place at 1284K for LC and at 1393K for MC on cooling at 10K/min. Secondary crystallization is observed at 976K for LC and at 877K for MC. The secondary crystalline phase for LC is defined as nepherine, but that for MC is not yet identified as a definite mineralogical phase. The observed crystallizing temperatures are in good agreement with exothermic peaks separately measured by DTA on cooling.

Summary To study the electrophoretic properties of milk proteins under conditions as nearly similar as possible to those found in milk, a paper strip electrophoresis apparatus was designed which required small volumes of electrolyte and in which electro-osmosis could be substantially reduced. Using this apparatus, it was shown that β -lactoglobulin could be isolated from milk, crystallized, and returned to its native environment without grossly affecting its initial charge density.

We have investigated the freezing of specimens in a confined volume for preparation of vitreous samples for cryosectioning. With 15% dextran as a cryoprotectant, a sample sealed in a copper tube begins to freeze into crystalline ice when plunged into liquid ethane. Crystallization rapidly causes an increase in the pressure to the point that much of the sample freezes in a vitreous state. We used synchrotron X-ray diffraction of samples frozen with various amounts of dextran to characterize the ice phases and crystal orientation, providing insights on the freezing process. We have characterized cryosections obtained from these samples to explore the optimum amount of cryoprotectant. Images of cryosectioned bacteria frozen with various levels of cryoprotectant illustrate effects of cryoprotectant concentration.

To comprehensively reuse copper ore tailings (COT), the fabrication of glass‐ceramics by the direct sintering method was investigated, where the residues after sulfur release and iron recovery from copper ore tailings were used as raw materials. The effect of the CaO added on the fabrication of glass‐ceramics was emphasized. After analysis of chemical composition and thermodynamics, crystallization kinetics were analyzed by Differential Scanning Calorimetry (DSC) and fitted to the Kissinger equation. The crystal phase and microstructure of sintered glass‐ceramics heated between 1080 °C and 1100 °C were estimated by X‐Ray diffraction analysis (XRD) and Scanning Electron Microscopy (SEM), respectively. Furthermore, the effects of the addition of CaO on the properties of the sintered glass‐ceramics have been discussed. The results showed that the magnetic glass‐ceramics were sintered by the residues successfully, the color of which was lighter than that of glass‐ceramics sintered by raw materials before iron recovery. According to the XRD analysis, hedenbergite, wollastonite and sekaninaite were formed with traces of maghemite and quartz. In terms of crystallization kinetics and sintering results, a decrease in the activation energies of crystallization and in sintering temperature were observed for an increase in the addition of CaO of up to 10 wt.%. Moreover, the properties of the sintered glass‐ceramics, including bulk density, linear shrinkage and flexural strength, were enhanced, while water absorption and true density were reduced with the increase of the amount of CaO added., Magnetic glass‐ceramics with good performance were fabricated successfully by direct sintering, using residues with a small amount of iron after sulfur release and iron recovery from copper ore tailings. Hedenbergite, wollastonite and sekaninaite were formed with traces of maghemite and quartz. Meanwhile, the color of the magnetic glass‐ceramics was lighter than that of glass‐ceramics sintered by raw materials before iron recovery.

RECENTLY, it has been obvious that in most biological materials N-acetylsialic acid (N-acetyl-neuraminic acid) and N-glycolloylsialic acid occur together. By the introduction of a micromethod for the determination of glycollic acid, Klenk and Uhlenbruck1 have made possible the evaluation of the amount of N-glycolloylsialic acid in isolated sialic acids. In search of a more direct method, we tried partition chromatography, employing the solvent systems previously used for the separation of sialic acids but with unfavourable results2,3. As the pK a of sialic acids are low, about pH 2.7, it is necessary to use rather a strong acid in the solvents to prevent the dissociation of the carboxylic group. Of the different acids tried, only trichloracetic acid and hydrochloric acid were suitable. On crystallization of the sialic acids we had observed that N-glycolloylsialic acid was much more insoluble in alcohols than N-acetylsialic acid. Therefore, we tried mixtures of alcohols with the acids mentioned above. The best results were obtained with n-butanol/n-propanol/ 0.1 N hydrochloric acid (1:2:1, v/v). In this solvent the R F values were for N-acetylsialic acid 0.45, and for N-glycolloylsialic acid 0.34, on Whatman paper No. 1. The solvent system applied cannot be used for the separation of diacetylsialic acids and is unsuitable for the separation of free acids and the methyl esters of the sialic acids.

Chemistry - a European journal 27(45), 11600 - 11608 (2021). doi:10.1002/chem.202101117, Amorphous Ti$_x$O$_y$ with high surface area has attracted significant interest as photocatalyst with higher activity in ultraviolet (UV) light-induced water splitting applications compared to commercial nanocrystalline TiO$_2$. Under photocatalytic operation conditions, the structure of the molecular titanium alkoxide precursor rearranges upon hydrolysis and leads to higher connectivity of the structure-building units. Structurally ordered domains with sizes smaller than 7 Å form larger aggregates. The experimental scattering data can be explained best with a structure model consisting of an anatase-like core and a distorted shell. Upon exposure to UV light, the white Ti$_x$O$_y$ suspension turns dark corresponding to the reduction of Ti$^{4+}$ to Ti$^{3+}$ as confirmed by electron energy loss spectroscopy (EELS). Heat-induced crystallisation was followed by in situ temperature-dependent total scattering experiments. First, ordering in the Ti−O environment takes place upon to 350 °C. Above this temperature, the distorted anatase core starts to grow but the structure obtained at 400 °C is still not fully ordered., Published by Wiley-VCH, Weinheim