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Size-resolved measurements of atmospheric aerosol and cloud condensation nuclei (CCN) concentrations and hygroscopicity were conducted over a full seasonal cycle at the remote Amazon Tall Tower Observatory (ATTO, March 2014–February 2015). In a preceding companion paper, we presented annually and seasonally averaged data and parametrizations (Part 1; Pöhlker et al., 2016a). In the present study (Part 2), we analyze key features and implications of aerosol and CCN properties for the following characteristic atmospheric conditions:Empirically pristine rain forest (PR) conditions, where no influence of pollution was detectable, as observed during parts of the wet season from March to May. The PR episodes are characterized by a bimodal aerosol size distribution (strong Aitken mode with DAit  ≈  70 nm and NAit  ≈  160 cm−3, weak accumulation mode with Dacc  ≈  160 nm and Nacc ≈  90 cm−3), a chemical composition dominated by organic compounds, and relatively low particle hygroscopicity (κAit ≈  0.12, κacc ≈  0.18).Long-range-transport (LRT) events, which frequently bring Saharan dust, African biomass smoke, and sea spray aerosols into the Amazon Basin, mostly during February to April. The LRT episodes are characterized by a dominant accumulation mode (DAit  ≈  80 nm, NAit  ≈  120 cm−3 vs. Dacc  ≈  180 nm, Nacc  ≈  310 cm−3), an increased abundance of dust and salt, and relatively high hygroscopicity (κAit ≈  0.18, κacc  ≈  0.35). The coarse mode is also significantly enhanced during these events.Biomass burning (BB) conditions characteristic for the Amazonian dry season from August to November. The BB episodes show a very strong accumulation mode (DAit  ≈  70 nm, NAit  ≈  140 cm−3 vs. Dacc  ≈  170 nm, Nacc  ≈  3400 cm−3), very high organic mass fractions ( ∼  90 %), and correspondingly low hygroscopicity (κAit ≈  0.14, κacc  ≈  0.17).Mixed-pollution (MPOL) conditions with a superposition of African and Amazonian aerosol emissions during the dry season. During the MPOL episode presented here as a case study, we observed African aerosols with a broad monomodal distribution (D  ≈  130 nm, NCN, 10  ≈  1300 cm−3), with high sulfate mass fractions (∼  20 %) from volcanic sources and correspondingly high hygroscopicity (κ ≈  0.14, κ > 100 nm ≈  0.22), which were periodically mixed with fresh smoke from nearby fires (D  ≈  110 nm, NCN, 10  ≈  2800 cm−3) with an organic-dominated composition and sharply decreased hygroscopicity (κ ≈  0.10, κ > 150 nm ≈  0.20).Insights into the aerosol mixing state are provided by particle hygroscopicity (κ) distribution plots, which indicate largely internal mixing for the PR aerosols (narrow κ distribution) and more external mixing for the BB, LRT, and MPOL aerosols (broad κ distributions).The CCN spectra (CCN concentration plotted against water vapor supersaturation) obtained for the different case studies indicate distinctly different regimes of cloud formation and microphysics depending on aerosol properties and meteorological conditions. The measurement results suggest that CCN activation and droplet formation in convective clouds are mostly aerosol-limited under PR and LRT conditions and updraft-limited under BB and MPOL conditions. Normalized CCN efficiency spectra (CCN divided by aerosol number concentration plotted against water vapor supersaturation) and corresponding parameterizations (Gaussian error function fits) provide a basis for further analysis and model studies of aerosol–cloud interactions in the Amazon.

Size-resolved long-term measurements of atmospheric aerosol and cloud condensation nuclei (CCN) concentrations and hygroscopicity were conducted at the remote Amazon Tall Tower Observatory (ATTO) in the central Amazon Basin over a 1-year period and full seasonal cycle (March 2014–February 2015). The measurements provide a climatology of CCN properties characteristic of a remote central Amazonian rain forest site.The CCN measurements were continuously cycled through 10 levels of supersaturation (S = 0.11 to 1.10 %) and span the aerosol particle size range from 20 to 245 nm. The mean critical diameters of CCN activation range from 43 nm at S = 1.10 % to 172 nm at S = 0.11 %. The particle hygroscopicity exhibits a pronounced size dependence with lower values for the Aitken mode (κAit = 0.14 ± 0.03), higher values for the accumulation mode (κAcc = 0.22 ± 0.05), and an overall mean value of κmean = 0.17 ± 0.06, consistent with high fractions of organic aerosol.The hygroscopicity parameter, κ, exhibits remarkably little temporal variability: no pronounced diurnal cycles, only weak seasonal trends, and few short-term variations during long-range transport events. In contrast, the CCN number concentrations exhibit a pronounced seasonal cycle, tracking the pollution-related seasonality in total aerosol concentration. We find that the variability in the CCN concentrations in the central Amazon is mostly driven by aerosol particle number concentration and size distribution, while variations in aerosol hygroscopicity and chemical composition matter only during a few episodes.For modeling purposes, we compare different approaches of predicting CCN number concentration and present a novel parametrization, which allows accurate CCN predictions based on a small set of input data.

The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, and biodiversity. It has already been changed significantly by human activities, and more pervasive change is expected to occur in the coming decades. It is therefore essential to establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, and atmospheric conditions and that will be operated over coming decades to monitor change in the Amazon region, as human perturbations increase in the future. The Amazon Tall Tower Observatory (ATTO) has been set up in a pristine rain forest region in the central Amazon Basin, about 150 km northeast of the city of Manaus. Two 80 m towers have been operated at the site since 2012, and a 325 m tower is nearing completion in mid-2015. An ecological survey including a biodiversity assessment has been conducted in the forest region surrounding the site. Measurements of micrometeorological and atmospheric chemical variables were initiated in 2012, and their range has continued to broaden over the last few years. The meteorological and micrometeorological measurements include temperature and wind profiles, precipitation, water and energy fluxes, turbulence components, soil temperature profiles and soil heat fluxes, radiation fluxes, and visibility. A tree has been instrumented to measure stem profiles of temperature, light intensity, and water content in cryptogamic covers. The trace gas measurements comprise continuous monitoring of carbon dioxide, carbon monoxide, methane, and ozone at five to eight different heights, complemented by a variety of additional species measured during intensive campaigns (e.g., VOC, NO, NO2, and OH reactivity). Aerosol optical, microphysical, and chemical measurements are being made above the canopy as well as in the canopy space. They include aerosol light scattering and absorption, fluorescence, number and volume size distributions, chemical composition, cloud condensation nuclei (CCN) concentrations, and hygroscopicity. In this paper, we discuss the scientific context of the ATTO observatory and present an overview of results from ecological, meteorological, and chemical pilot studies at the ATTO site.

In recent years process modelling has become an established method which generates digital twins of manufacturing plant operation with the aid of numerically solved process models. This article discusses the benefits of establishing process modelling, in-house or by cooperation, in order to support the workflow from process development, piloting and engineering up to manufacturing. The examples are chosen from the variety of botanicals and biologics manufacturing thus proving the broad applicability from variable feedstock of natural plant extracts of secondary metabolites to fermentation of complex molecules like mAbs, fragments, proteins and peptides.Consistent models and methods to simulate whole processes are available. To determine the physical properties used as model parameters, efficient laboratory-scale experiments are implemented. These parameters are case specific since there is no database for complex molecules of biologics and botanicals in pharmaceutical industry, yet.Moreover, Quality-by-Design approaches, demanded by regulatory authorities, are integrated within those predictive modelling procedures. The models could be proven to be valid and predictive under regulatory aspects. Process modelling does earn its money from the first day of application. Process modelling is a key-enabling tool towards cost-efficient digitalization in chemical-pharmaceutical industries.

The transition towards a bio-based world is a challenging undertaking. This perspective paper, from an engineering point of view, aims to provide an overview of existing projects and academic disciplines highlighting the potential benefit of increased interdisciplinary exchanges. Furthermore, the current utilization of biomass to produce biogas is discussed, including an economic assessment, showing the need for new strategies of biomass valorization. One solution could be the development of separation processes for the isolation of secondary plant metabolites, which have been especially valuable for pharmaceutical applications, e.g., taxotere ® and artemisinin. The economic feasibility is demonstrated in a case study, evaluating the purification potential of curcuminoids from Curcuma longa L. Subsequently, the conclusion discusses the limitations of large-scale industrial applications and the need for new separation techniques as a step towards a bio-based world.

A steady increase of product titers and the corresponding change in impurity composition represent a challenge for development and optimization of antibody production processes. Additionally, increasing demands on product quality result in higher complexity of processes and analytics, thereby increasing the costs for product work-up. Concentration and composition of impurities are critical for efficient process development. These impurities can show significant variations, which primarily depend on culture conditions. They have a major impact on the work-up strategy and costs. The resulting "bottleneck" in downstream processing requires new optimization, technology and development approaches. These include the optimization and adaptation of existing unit operations respective to the new separation task, the assessment of alternative separation technologies and the search for new methods in process development. This review presents an overview of existing methods for process optimization and integration and indicates new approaches for future developments.

Liquid chromatographic methods cover the broadest range of applications imaginable today. Nowhere is this more evident and relevant than in the life sciences, where identification of target substances relevant in disease mechanisms is performed down to the femtomole level. On the other hand, purification of therapeutic drugs on a multi-ton scale is performed by process LC. The complexity and abundance range of biological systems in combination with the extreme purity requirements for drug manufacturing are the challenges that can be mastered today by chromatography, after more than a century of research and development. However, significant improvement is still required for a better understanding of the scientific fundamentals of the underlying phenomena and exploiting those for an enhanced quality of live.

A compact, double-sided laser-heating system for diamond-cell synchrotron applications is described. The optical table, containing laser, spectrometer, and all optics for visual observation and measuring temperatures and pressures has an area of less than 1/2 m(2) and weighs less than 20 kg. All components can be remotely controlled at micron levels with simple dc motors and pneumatic drives. The design allows quick alignment of the laser-heated hot spot with the x-ray beam and the spectrometer. The prealigned system can be set up at most synchrotron beamlines within about 1 h. We carried out measurements on a variety of materials above one megabar and up to over 4000 K at both the x-ray diffraction beamline ID 27 and the x-ray absorption beamline ID 24 at the European Synchrotron Facility. A new measurement of the melting temperature of iron by x-ray absorption spectroscopy is presented.

Oligonucleotide-loaded nanoparticles, which are of interest for biomedical application, up to now, could not be prepared by in-situ synthesis, due to difficulty of handling in automated synthesizers. To overcome this problem, we have introduced the "support-on-support" concept. It is based on the reversible anchoring of nanoparticles to the surface of microparticles. These composite beads easily can be used for automated synthesis, being released after completion of chain elongations. As examples, dextran-coated magnetite nanoparticles were attached to polystyrene microparticles through (1) a gelatine or (2) a silica layer. Release involved dissolution of the bonding layer by (1) proteases or (2) alkali.