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Due to surface effects and quantum size effects, nanomaterials have properties that are vastly different from those of bulk materials due to surface effects. The particle size distribution plays an important role in chemical and physical properties. The measurement and control of this parameter are crucial for nanomaterial synthesis. Dynamic light scattering (DLS) is a fast and non-invasive tool used to measure particle size, size distribution and stability in solutions or suspensions during nanomaterial preparation. In this review, we focus on the in situ sizing of nanomaterial preparation in the form of colloids, especially for metal oxide nanoparticles (MONs). The measuring principle, including an overview of sizing techniques, advantages and limitations and theories of DLS were first discussed. The instrument design was then investigated. Ex-situ and in situ configuration of DLS, sample preparations, measurement conditions and reaction cell design for in situ configuration were studied. The MONs preparation monitored by DLS was presented, taking into consideration both ex situ and in situ configuration.

A comprehensive understanding of the deposition mechanisms and morphology of debris flows is necessary to delineate the extent of a debris flow hazard. However, due to the wide range of debris flow compositions and the complex topography in the field, there remains a deficiency of fundamental understanding on how the effects of grain-size distribution, water content, and channel slope influence the deposition mechanisms and morphology of debris flow. In this study, a series of experimental tests were carried out using a flume with a horizontal outflow plane to discern the effects of particle size, water content, and slope on the deposition morphology and grain size segregation on the deposition fan. Results reveal that the experimental debris flows are under either viscous or collisional flow regimes. Most experimental debris flow fronts lack high pore fluid pressures, emphasizing the formation of deposits via grain-grain and grain-bed friction and collisions; also high excess pore fluid pressure (positive) behind the front head is measured and it is beneficial for the mobility of debris flows. Both the deposit area and runout-width ratio are positively correlated to the Bagnold and Savage numbers and the initial water contents. Furthermore, an increase of fines content reduces the runout distance. However, this feature is not as obvious for high water content flows (w = 28.5% in this study). Moreover, smoother transition topography between the transportation and deposition zone leads to longer runout distances. For debris flows with a high solid fraction (Cs > 0.52 in this study), particle sorting is quite inhibited in the deposit fan.

The strong metal-support interaction (SMSI) has long been studied in heterogonous catalysis on account of its importance in stabilizing active metals and tuning catalytic performance. As a dynamic process taking place at the metal-support interface, the SMSI is closely related to the metal surface properties which are usually affected by the size of metal nanoparticles (NPs). In this work we report the discovery of a size effect on classical SMSI in Au/TiO 2 catalyst where larger Au particles are more prone to be encapsulated than smaller ones. A thermodynamic equilibrium model was established to describe this phenomenon. According to this finding, the catalytic performance of Au/TiO 2 catalyst with uneven size distribution can be improved by selectively encapsulating the large Au NPs in a hydrogenation reaction. This work not only brings in-depth understanding of the SMSI phenomenon and its formation mechanism, but also provides an alternative approach to refine catalyst performance. Strong metal-support interaction (SMSI) is critical in determining the catalytic performance of supported metal catalysts. Here the authors report a phenomenon of size-dependent classical SMSI in Au/TiO 2 catalyst where larger Au particles are more prone to be encapsulated than smaller ones.

The concept of sustainable and responsible (SR) investments expresses that every investment should be based on the SR investor's code of ethics. To a large extent the allocation of SR investments to more sustainable companies and ethical practices is based on the environmental, social, and corporate governance (ESG) scores provided by rating agencies. However, a thorough investigation of ESG scores is a neglected topic in the literature. This paper uses Thomson Reuters ASSET4 ESG ratings to analyze the influence of firm size, a company's available resources for providing ESG data, and the availability of a company's ESG data on the company's sustainability performance. We find a significant positive correlation between the stated variables, which can be explained by organizational legitimacy. The results raise the question of whether the way the ESG score measures corporate sustainability gives an advantage to larger firms with more resources while not providing SR investors with the information needed to make decisions based on their beliefs. Due to our results, SR investors and scholars should reopen the discussion about: what sustainability rating agencies measure with ESG scores, what exactly needs to be measured, and if the sustainable finance community can reach their self-imposed objectives with this measurement.

The application of biochar is promising for improving the physical, chemical and hydrological properties of soil. However, there are few studies regarding the influence of biochar particle size. This study was conducted to evaluate the effect of biochar size on the physical, chemical and hydrological properties in sandy and loamy tropical soils. For this purpose, an incubation experiment was conducted in the laboratory with eight treatments (control (only soil), two soils (loamy and sandy soil), and three biochar sizes (<0.15 mm; 0.15–2 mm and >2 mm)). Analyses of water content, bulk density, total porosity, pore size distribution, total carbon (TC) and total N (TN) were performed after 1 year of soil–biochar-interactions in the laboratory. The smaller particle size <0.15 mm increased water retention in both soils, particularly in the loamy soil. Bulk density slightly decreased, especially in the loamy soil when biochar > 2 mm and in the sandy soil with the addition of 0.15–2 mm biochar. Porosity increased in both soils with the addition of biochar in the range of 0.15–2 mm. Smaller biochar particles shifted pore size distribution to increased macro and mesoporosity in both soils. Total carbon content increased mainly in sandy soil compared to control treatment; the highest carbon amount was obtained in the biochar size 0.15–2 mm in loamy soil and <0.15 mm in sandy soil, while the TN content and C:N ratio increased slightly with a reduction of the biochar particle size in both soils. These results demonstrate that biochar particle size is crucial for water retention, water availability, pore size distribution, and C sequestration.

Allometry refers to the size-related changes of morphological traits and remains an essential concept for the study of evolution and development. This review is the first systematic comparison of allometric methods in the context of geometric morphometrics that considers the structure of morphological spaces and their implications for characterizing allometry and performing size correction. The distinction of two main schools of thought is useful for understanding the differences and relationships between alternative methods for studying allometry. The Gould–Mosimann school defines allometry as the covariation of shape with size. This concept of allometry is implemented in geometric morphometrics through the multivariate regression of shape variables on a measure of size. In the Huxley–Jolicoeur school, allometry is the covariation among morphological features that all contain size information. In this framework, allometric trajectories are characterized by the first principal component, which is a line of best fit to the data points. In geometric morphometrics, this concept is implemented in analyses using either Procrustes form space or conformation space (the latter also known as size-and-shape space). Whereas these spaces differ substantially in their global structure, there are also close connections in their localized geometry. For the model of small isotropic variation of landmark positions, they are equivalent up to scaling. The methods differ in their emphasis and thus provide investigators with flexible tools to address specific questions concerning evolution and development, but all frameworks are logically compatible with each other and therefore unlikely to yield contradictory results.

An impact-type Joss-Waldvogel disdrometer (JWD), a two-dimensional video disdrometer (2DVD), and a laser optical OTT Particle Size and Velocity (PARSIVEL) disdrometer (PD) were used to measure the raindrop size distribution (DSD) over a 6-month period in Huntsville, Alabama. Comparisons indicate event rain totals for all three disdrometers that were in reasonable agreement with a reference rain gauge. In a relative sense, hourly composite DSDs revealed that the JWD was more sensitive to small drops (,1 mm), while the PD appeared to severely underestimate small drops less than 0.76mm in diameter. The JWD and 2DVD measured comparable number concentrations of midsize drops (1-3mm) and large drops (3-5 mm), while the PD tended to measure relatively higher drop concentrations at sizes larger than 2.44mm in diameter. This concentration disparity tended to occur when hourly rain rates and drop counts exceeded 2.5mm/h and 400/min, respectively. Based on interactions with the PD manufacturer, the partially inhomogeneous laser beam is considered the cause of the PD drop count overestimation. PD drop fall speeds followed the expected terminal fall speed relationship quite well, while the 2DVD occasionally measured slower drops for diameters larger than 2.4mm, coinciding with events where wind speeds were greater than 4m/s. The underestimation of small drops by the PD had a pronounced effect on the intercept and shape of parameters of gamma-fitted DSDs, while the overestimation of midsize and larger drops resulted in higher mean values for PD integral rain parameters

In response to the green development concept of the textile industry, this article describes the development of a biodegradable and eco-friendly raw starch sizing agent formulation. The sizing agent performance, sizing quality, biodegradation, weave efficiency, and production cost of the raw starch formulation in raw starch sizing process were compared with three other formulations. The results showed that the formulation prepared with raw starch achieved a lower viscosity and higher stability compared with the other three formulations. The raw starch sizing exhibited excellent moisture regain, moisture absorption performance and breaking strength, high enhancement rate and low elongation, high penetration, low coating, and abrasion resistance. The raw starch formulation was shown to be energy-saving and environmentally friendly, with higher weave efficiency and lower production costs. The BOD5/COD was 0.65, which means that the desizing wastewater is easy to degrade. Sizing agent cost was 17 to 61% lower and loom efficiency was 5% to 12% higher. This research provides a theoretical basis for promoting the usage of raw starch sizing in practical production, which contributes to green and eco-friendly processing.

The process and efficiency of sizing aramid yarns before the weaving process was studied. The sizing was carried out under different conditions, with and without the pre-wetting of the threads before the actual sizing process. Two groups of yarns were tested. The first group consisted of five yarn samples that were blended with 95% meta-aramid and 5% para-aramid in counts of 20 × 2, 17 × 2, 14 × 2 and 12.5 × 2 tex. The second group of yarns consisted of three yarn samples that were blended with 93% meta-aramid, 5% para-aramid and 2% carbon in counts of 20, 20 × 2 and 17 × 2 tex. The inlet moisture of the yarn before sizing was 40% (with pre-wetting) and 4% (without pre-wetting), and the outlet moisture after drying was 4%. In order to carry out such tests to reproduce them, the sizing was carried out on a laboratory-sizing machine with the possibility of adapting to industrial conditions. According to the obtained results related to the properties of yarn before and after sizing, it can be concluded that sizing of aramid yarns is justified. When sizing the yarn without pre-wetting, the mechanical properties improved, especially breaking force, strength and abrasion resistance. Irregularity and hairiness were also reduced, especially when sizing with pre-wetting. Yarn hairiness or the frequency of protruding fibres also decreased with sizing in almost all samples and sizing conditions. The second group of yarns with a carbon fibre content mostly showed better mechanical properties before sizing, which continued after sizing. In general, the aramid yarn sized with pre-wetting showed certain deformations caused by stretching in the wet state and thus reduced the size pick-up, which caused less breaking forces and strength. Sizing with pre-wetting resulted in a slightly better smoothness of the thread and its higher evenness. It can be concluded that the aramid yarn should be sized with a lower size percentage (up to 4.5%), i.e., without pre-wetting in order to minimise the deformation of the yarn during sizing and thus improve the mechanical properties in the weaving process.

Background/Objectives: Controlling food portion sizes can help reduce energy intake, but the effect of different portion-control methods on weight management is not known. In a 1-year randomized trial, we tested whether the efficacy of a behavioral weight-loss program was improved by incorporating either of the two portion-control strategies instead of standard advice about eating less. Subjects/Methods: The Portion-Control Strategies Trial included 186 women with obesity (81%) or overweight (19%). Participants were randomly assigned to one of three equally intensive behavioral programs, consisting of 19 individual sessions over 12 months. The Standard Advice Group was instructed to eat less food while making healthy choices, the Portion Selection Group was instructed to choose portions based on the energy density using tools such as food scales and the Pre-portioned Foods Group was instructed to structure meals around pre-portioned foods such as single-serving main dishes, for which some vouchers were provided. In an intention-to-treat analysis, a mixed-effects model compared weight loss trajectories across 23 measurements; at month 12, weight was measured for 151 participants (81%). Results: The trajectories showed that the Pre-portioned Foods Group initially lost weight at a greater rate than the other two groups ( P =0.021), but subsequently regained weight at a greater rate ( P =0.0005). As a result, weight loss did not differ significantly across groups at month 6 (mean±s.e. 5.2±0.4 kg) or month 12 (4.5±0.5 kg). After 1 year, measured weight loss averaged 6% of baseline weight. The frequency of using portion-control strategies initially differed across groups, then declined over time and converged at months 6 and 12. Conclusions: Incorporating instruction on portion-control strategies within a 1-year behavioral program did not lead to a greater weight loss than standard advice. Using pre-portioned foods enhanced early weight loss, but this was not sustained over time. Long-term maintenance of behavioral strategies to manage portions remains a challenge.