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Bioavailability of zinc (Zn) can be estimated by desorption in sandy loam soil for sustainable nutrient delivery technology by nutrient carriers. While being renewable and biodegradable in nature, wood derivatives have a high potential to offer numerous benefits of a hierarchical pore network, mechanical stability, and facile adsorption–desorption properties. High-altitude wood offers higher wood density that forms carbon frameworks with rich and indefinite numbers of open and low-tortuosity cavities decorated with longer tube-like channels which facilitate infiltration of nutrient ions via permeation. Wood-derived carbon frameworks with longer tube-like channels can facilitate zinc salt (ZnSO4·7H2O) permeation for adsorption–desorption kinetics of Zn-nutrient release and flow in a model system. The wood-derived carbon framework of an ultrathick porous nature with long channels was developed by thermal pretreating to access to carbon-wood (CW) followed by carbonization to obtain CW-HCN to increase the active site of Zn-salt adsorption. The CW framework was dipped into a metal salt precursor solution of FeCl2(anhydrous) or (FeCl2+ ZnCl2) followed by drying, which allowed rapid self-assembling of metal salts in a CW framework while allowing exposure to a heat-pulse treatment during pyrolysis. The desorption characteristics of Zn were analyzed from rapid initial desorption until equilibration in 8 h, and thereafter a slow-release rate was noticed.

The objective of this study was to assess the long-term cumulative effects of forest land use on soil properties under four forests, Chir pine (Pinus roxburghii), Deodar (Cedrus deodara), Oak (Quercus leucotrichophora) and mixed (Chir Pine + Deodar) forest. Tree litter samples were drawn from each of forest by forming a 1 m × 1 m quadrant. Litter sampling was done at three months interval in a year. Tree biomass estimation was done by laying 10 m × 10 m quadrant for each forest site, and DBH (Diameter at Breast Height) of all trees within quadrate was recorded. Soil sample was randomly collected at soil depth of 0–15 (surface layer) and 15–30 cm (sub-surface layer) in triplicate in each forest for two successive years. The sampling and analysis of soil and plant was done during 2016–2017 and 2017–2018. Biomass production varied from 28.01 to 156.64 Mg ha−1. Total carbon (soil + biomass) in mixed forest was highest (89.9 Mg ha−1) and the least in deodar (39.21 Mg ha−1). Soil under Oak plantation contributed more carbon (64.5%) to the total carbon (C). Soil organic carbon (SOC) in surface soil was higher in oak (29.73 g kg−1) followed by deodar, pine and the least (9.9 g kg−1) in mixed forest. Highest BD was observed in surface soils of mixed forest (1.52 Mg m−3), and it was lowest in surface (1.11 Mg m−3) as well as in sub-surface (1.13 Mg m−3) soils of oak forests. Total porosity in surface layer was maximum (53.17%) in Oak forests and minimum (39.39%) in mixed forests. Soil bulk density, particle density and aggregate bulk density followed order mixed > chir pine > deodar > oak. Pearson correlation analysis revealed significant negative relationship between SOC and bulk density. Thus, keeping in view ecological benefits of forests, assessment of parameters like biomass, SOC and other soil physical parameters like particle density, bulk density, total porosity, maximum water holding capacity, mean weight diameter and field capacity will help in designing strategies for long-term sustainable management of forest ecosystems.

The fundamental thermodynamic property of a cocrystal is its formation energy, often referred to as Gibbs free energy of formation, ΔGf, which is essential to provide insights into its preparation and stability. Most experimental methods of determining ΔGfof a cocrystal from its solubility and those of the pure components assume ideal intermolecular interactions among the components, i.e., where the strength and nature of interactions between different components are regarded identical with those in the pure components. However, in most real systems of interest, the interactions between the cocrystal components and their interactions with the solvent often deviate from ideality because of differences in polarity, hydrogen-bonding propensity, and dispersion forces, leading to nonideal mixing effects on their properties. In this article, a ternary phase diagram (TPD) is utilized to elucidate how nonideal mixing among the components affect the ΔGfdetermination of cocrystals and a simple equation is proposed to determine the same. Additionally, the use of a TPD in determining ΔGfvalues of a few cocrystals is described using this equation. The significance and limitations of the derived equation in determining ΔGfare also discussed.

Manufacturing a specified polymorphic form of an active pharmaceutical ingredient (API) is of immense importance in the pharmaceutical industry. Crystal polymorphism and transformations among different forms of APIs are studied in detail during process development. While associated impurities in API are characterized in depth for their chemical structures and properties, solid state characteristics of impurities are usually overlooked, mainly because of their presence in low levels. Herein, we discuss a case of a process impurity, BrettPhos oxide (BPO), interfering with in-process phase analysis of an API. The impact of changing the workup procedure on the impurity purging and its effect on solid form analysis of the API is highlighted. Complexities encountered due to interplay between different solid forms of BPO and API are presented. Further, phase behavior of BPO in some common process relevant solvents is established.

Crop yields in sandy soils can be increased by addition of clay-rich soil, but little is known about the effect of clay addition on nutrient availability after addition of plant residues with different C/N ratios. A loamy sandy soil (7% clay) was amended with a clay-rich subsoil (73% clay) at low to high rates to achieve soil mixtures of 12%, 22%, and 30% clay, as compared to a control (sandy soil alone) with no clay addition. The sandy-clay soil mixtures were amended with finely ground plant residues at 10 g kg−1: mature wheat (Triticum aestivumL.) straw with a C/N ratio of 68, mature faba bean (Vicia fabaL.) straw with a C/N ratio of 39, or their mixtures with different proportions (0%–100%, weight percentage) of each straw. Soil respiration was measured over days 0–45 and microbial biomass C (MBC), available N, and pH on days 0, 15, 30, and 45. Cumulative respiration was not clearly related to the C/N ratio of the residues or their mixtures, but C use efficiency (cumulative respiration per unit of MBC on day 15) was greater with faba bean than with wheat and the differences among the residue mixtures were smaller at the highest clay addition rate. The MBC concentration was lowest in sole wheat and higher in residue mixtures with 50% of wheat and faba bean in the mixture or more faba bean. Soil N availability and soil pH were lower for the soil mixtures of 22% and 30% clay compared to the sandy soil alone. It could be concluded that soil cumulative respiration and MBC concentration were mainly influenced by residue addition, whereas available N and pH were influenced by clay addition to the sandy soil studied.

The Gibbs energy of formation, ΔGf, of a cocrystal is a fundamental property to determine its thermodynamic stability. One of the methods to determine ΔGfis from the eutectic composition of the components of the cocrystal in a given solvent. However, conventional methods to determine the ΔGfof a cocrystal from the eutectic composition in a given solvent are indicated to be valid when it dissociates into an unsolvated (or anhydrous) form of the components in that solvent. This article explores the condition when the ΔGfof a cocrystal may be calculated from its eutectic composition in a solvent where the thermodynamically stable form of one of the components is a hydrate. The theophylline–nicotinamide cocrystal, which dissociates into theophylline hydrate and nicotinamide in water, is used as the model cocrystal in this study. The calculated ΔGfvalues of the cocrystal from water are compared with those obtained from the eutectic composition of the cocrystal in nonsolvate forming solvents, namely, ethyl acetate and 2-propanol. The implication of the study in pharmaceutical development of cocrystal is discussed.