“La Sorbella” is a deep-seated existing landslide in a Miocene clayey formation located in central Italy. Given the interaction with a national road, this landslide has been monitored for a long time with inclinometers and hydraulic piezometers. Recently, the monitoring system was implemented by adding pressure transducers in the Casagrande cells and by equipping the old inclinometers with in-place probes, to allow a remote reading of the instruments and data recording. This system allowed to identify that the very small average rate of movement observed over one year (1.0–1.5 cm/year) is the sum of small single sliding processes, strictly linked to the sequence of rainfall events. Moreover, data recorded by in-place inclinometer probes detected the response of the landslide to the seismic sequence of 2016 occurring in central Italy. Such in situ measurements during earthquakes, indeed rarely available in the scientific literature, allowed an assessment of the critical acceleration of the sliding mass by means of a back-analysis. The possibility to distinguish the difference between seismic and rainfall induced displacements of the slope underlines the potential of continuous monitoring in the diagnosis of landslide mechanisms.
Process safety groups in the pharmaceutical industry are important components of active pharmaceutical ingredient (API) development through its life cycle from discovery to commercial scale. The pharmaceutical process safety laboratory staff conduct a series of tests to identify chemically unstable reagents, intermediates and solvents, and mixtures to ensure that the proposed operating conditions provide a sufficient safety margin from the onset of undesired and potentially catastrophic thermal decomposition. Across several pharmaceutical companies, the methods used for these assessments and how results and conclusions are made are widespread (vide infra). A working group was created with members from several pharmaceutical companies within the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ), with the goal of precompetitive collaboration and to understand each of the participating companies’ procedures and assessment regarding process safety. Each company was invited to provide input using a blind survey format. This was done in the interest of making this knowledge accessible for the participating companies and the wider community of other pharma and chemical companies and even academic institutions in the US and throughout the world. This article provides the results of this in-depth survey of the members of the IQ Consortium thermal hazard working group. General issues around different tools used to assess thermal hazard risk and questions regarding staffing and tech transfer of process safety data/information from development to manufacturing were addressed. A snapshot of how various assessment strategies are employed as a function of stage of development (early, mid, and late) is also presented.
A special class of biochemical reactions involves a set of enzymes that generate additional copies of themselves and transfer heritable information from parent to progeny molecules, thus providing the basis for genetics and Darwinian evolution. Such a process has been realized with a pair of self-replicating RNA enzymes that undergo exponential amplification at constant temperature. Exponential growth requires that the rate of production of new enzymes be directly proportional to the existing concentration of enzymes, which is the case for this system and provides a doubling time of ~20 min. However, the catalytic rate of the underlying enzymes is ~100-fold faster than the observed rate of replication. As in biological replication, other aspects of the system limit the generation time, chiefly the propensity of the substrate molecules to form non-productive complexes that limit their availability for replication. An analysis of this and other kinetic properties of the self-replicating RNA enzymes reveals how exponential amplification is achieved and how the rate of amplification might be increased.
Reaction calorimetry can be employed for kinetic studies of complex catalytic reactions. In the calorimeter, the enthalpy balance around the reactor is continuously monitored and gives a profile of reaction heat vs time, which can be easily expressed in terms of reaction rate, conversion, and concentration of reactants/products. The data can be further analyzed using a methodology called reaction progress kinetic analysis, where the rate is expressed in terms of the concentration of substrates and a graphical expression is used to analyze the order in each substrate and in the catalyst. When studying a catalytic cycle, we can obtain useful information on catalyst activation/deactivation, substrate or product activation/deactivation, and the rate-limiting step. Thus, a detailed mechanistic picture can be obtained. In the present work we show an example of the role of reaction calorimetry in both fingerprinting and detailed study of some Pd-catalyzed aminations of aryl halides. These reactions are considered to be a very important route in making substituted aromatic amines. We observe how the overall kinetics of the reaction changes when changing the amine; the explanation takes into account the mechanism and proposes a change in the rate-limiting step.
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