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Real-time monitoring of critical quality attributes, such as residual water in granules after drying which can be determined through loss-on-drying (LOD), during wet granulation and drying is essential in continuous manufacturing. Near-infrared (NIR) spectroscopy has been widely used as process analytical technology (PAT) for in-line LOD monitoring. This study aims to develop and apply a model for predicting the LOD based on process parameters. Additionally, the efficacy of an orthogonal PAT approach using NIR and mass balance (MB) for a vibrating fluidized bed dryer (VFBD) is demonstrated. An in-house-built, cost-effective NIR sensor was utilized for measurements and exhibited good correlation compared to standard method via infrared drying. The combination of NIR and MB, as independent methods, has demonstrated their applicability. A good correlation, with a Pearson r above 0.99, was observed for LOD up to 16 % (w/w). The use of an orthogonal PAT method mitigated the risk of false process adaption. In some experiments where the NIR sensor might have been covered by powder and therefore did not measure accurately, LOD monitoring via MB remained feasible. The developed model effectively predicted LOD or process parameters, resulting in an R2 of 0.882 and a RMSE of 0.475 between predicted and measured LOD using the standard method. [Display omitted] • Implementation of an orthogonal process analytical technology approach for loss-on-drying monitoring using near-infrared spectroscopy and mass balance within a vibrated fluidized bed dryer. • Loss-on-drying prediction model based on key process parameters was developed and verified. • Demonstrated the feasibility of predicting a process parameter to achieve a desired moisture content. • Low-cost, in-house built near infrared spectroscopy sensor correlated good with the measurement via mass balance. [ABSTRACT FROM AUTHOR]

This article presents millimeter wavelength measurements of the mass normalized extinction cross section (extinction efficiency) of thin copper circular discs at broadside incidence. The extinction efficiencies of the discs were measured as a function of diameter and thickness at a fixed frequency of 35 GHz. The measurements cover a wide range of diameters and thicknesses and were compared with the approximate numerical solution of the problem provided by the CWW code. A good agreement between the measurements and CWW code was achieved after applying the extinction paradox for small particles with high index of refraction to the CWW code calculations. [ABSTRACT FROM AUTHOR]

There are many studies on the effect of side wall friction on mass discharge rate (MDR), but the physical mechanism is lacking. In this paper, by changing side wall friction of eccentric silos, the relationship between macroscopic MDR and microscopic frictional coefficient was established, and the regulation of MDR up to a range of 40 % was realized. Furthermore, it is revealed that the variation of MDR is caused by the change in geometric structure of free-fall arch (FFA). In addition, the velocity of particles on FFA is the same under different MDR. The reason is that under high frictional coefficient, the gravitational potential energy of particles is more dissipated in the rotational motion caused by resistance. This work explains for the first time the mechanism of the frictional coefficient on MDR, and provides a data reference for improving the theoretical model of MDR. Measurement results of mass discharge rate and free-fall arch. [Display omitted] • The regulation of MDR up to a range of 40 % is realized in eccentric silo. • The effect of low frictional coefficient on MDR is significant than that of higher. • Variable side wall can regulate MDR by adjusting the area of free fall region. • Higher frictional coefficient makes particles undergo additional rotational motion. [ABSTRACT FROM AUTHOR]

• Establish a geometric correction factor algorithm based on the weight's shape. • Develop a novel and systematic model for evaluating and analyzing the uncertainty of magnetic measurement results of weights. • Conduct a comparative analysis with magnetic measurement uncertainty evaluation models of weights among different National Metrology Institutes to demonstrate the feasibility of the measurement model in this study. • The uncertainty of magnetic measurement of weights mainly comes from the magnetic moment m d and magnetic field gradient B Ez of the magnetic susceptibility meter's permanent magnet. • Consider the influence of environmental factors in the uncertainty analysis of magnetic measurement results. The magnetism of weights is an important factor affecting the accuracy of mass measurement, and the magnetic susceptibility and polarization intensity of weights are key indicators for measuring their magnetism. There is a lack of comprehensive and systematic methods to evaluate and analyze the uncertainty of magnetic measurement results of weights. This research established a weight magnetic analysis measurement model in high-accuracy mass measurements to address this issue, evaluated the uncertainty of the magnetic measurement results of the weight, and compared the results with those of multiple measurement mechanisms. After analysis, it was found that the uncertainty of the magnetic measurement results of the weight mainly comes from the magnetic moment m d and magnetic field gradient B Ez of the permanent magnet of the magnetic susceptibility meter. [ABSTRACT FROM AUTHOR]

In recent years, concerns about the health and environmental risks associated with PM 1 particles have increased. However, existing PM 1 sampling instruments remain to be improved mainly because their PM 1 inlets have particle loading and bounce issues. To address these challenges, PM 1 inlets based on the Non-Bouncing Impactor (NBI) technique were developed. These inlets employ vacuum oil-wetted glass fiber filter (GFF) substrates to eliminate particle bounce and incorporate a daily vacuum oil injection to prevent particle loading. The 16.7 L/min PM 1 NBI, modified from the PM 2.5 M-WINS design with a reduced diameter of the single nozzle, was designed to adapt readily with current standard sampling and monitoring systems. The cut-size (D pa50) of 0.99 ± 0.02 μm was determined by considering the effects of Reynold number and the ratio of jet-to-plate distance and nozzle diameter. Field tests comparing the 16.7 L/min PM 1 NBI sampler to the 9-stage NCTU Micro-orifice Cascade Impactor (NMCI 9) revealed small sampling biases, with a mean difference of +0.26 ± 2.28 μg/m3 for PM 1 measurements when silicone oil-coated aluminum foil (AF) and GFF-AF were used in the NMCI 9. The NBI with the oil-wetted GFF substrate effectively removed particles larger than 1.0 μm, resulting in more accurate PM 1 mass concentration measurements. Additionally, the development of a 5-stage NMCI with the 30 L/min PM 1 NBI as the first stage enabled detailed measurement of PM 1 mass distribution in two modes, which was challenging when measuring the entire mass distribution of ambient aerosols. The distribution of size-dependent water-soluble inorganic ions in PM 1 showed dominance of SO 4 2− and NH 4 + in PM 1 compared to PM 2.5. In summary, the PM 1 NBI enhances accuracy for long-term atmospheric sampling by addressing particle loading and bounce, making it a more reliable standard sampling instrument. [Display omitted] • A 16.7 L/min Non-Bouncing Impactor (NBI) was developed with excellent cutoff characteristics (D pa50 = 0.99 μm). • The 16.7 L/min NBI can easily replace the existing PM 2.5 inlets and adapt readily to the current FRM samplers and FEM monitors. • The 30 L/min NBI was developed and used as the first stage of a 5-stage cascade impactor to remove particles larger than 1.0 μm. • The 5-stage NMCI-NBI enables detailed measurement of PM 1 mass distribution in two modes and its chemical composition. [ABSTRACT FROM AUTHOR]