Influence of the Temperature on Coccolith-Containing Systems from Emiliania huxleyi Cultivations

Thermogravimetric analysis of a coccolith-containing biogenic broth showed a three-step degradation process. According to this system behavior, the biogenic broth was heated to specific temperatures and characterized in terms of its morphology, surface chemistry, and crystallinity. The elemental and organic composition of the treated samples was also evaluated and compared to the reference material. The presented results were acquired in an effort to exploit pretreatment scenarios for such a biogenic system that would improve and support a separation process.     

Shortcut assessment of alternative distillation sequence schemes for process intensification

Finding good process schemes is a difficult task due to its search among multiple alternatives. In literature, several methods are successfully implemented as computer tools, but their use is limited to their developers. There are several useful rules of thumb and heuristics providing useful guidelines, but sometimes these are contradictory. Some authors tried to rank the various alternatives, defining heuristic equations to provide a quantitative parameter to choose among possible solutions. In this paper, mathematical model of distillation columns is simplified, assuming infinite number of stages. The resulting proposed equation has a great similarity to one of the previous heuristic ones. A simple equation not relying on heuristics and easy to use in calculation is provided to evaluate the distillation sequence energy efficiency (DSE) for each alternative. This allows to quantify the advantages derived from process intensification for a given feed composition. The proposed equation is dimensionless, as the Carnot efficiency is used instead of the temperature difference between distillate and bottoms. On the other hand, intermediate results provide also useful information. For instance, the Carnot efficiency of each column indicates when a heat pump or enhanced distillation would be useful. The recovery efficiency for each particular compound allows an easy comparison between alternatives, considering variations on the feed composition. The new equation is verified comparing its results with cases already solved in literature using different methods. The results show that all the methods in literature are able to provide the best sequence, except the heuristics-based ones that are not providing an overall sequence evaluation. The novelty of the proposed DSE method resides in its ease of application, compared to nowadays available methods, and requires only the feed composition and products boiling points.     

Production Rate‐Dependent Key Performance Indicators for a Systematic Design of Biochemical Downstream Processes

Key performance indicators have become a common tool in bioprocess development, as they allow an objective and independent rating and ranking of process alternatives screened. A disadvantage of all key performance indicators developed so far is their strong focus on costs, which makes them neglect the influence of the production rate on the profit of the process. But, since both production costs and production rate have an equally strong impact, both should be considered when decisions have to be made. Therefore, two new key performance indicators are introduced in this work, one for batch and one for continuous processing. They combine product yield, purity performance, variable manufacturing costs, and production rate to one objective. Thereby, misguided trade‐offs between these four individual measures can be replaced by one key performance indicator. This ensures a systematic development of biochemical downstream processes.     

Empirical analysis of GUI programming concerns

The focus of this paper is on identification of typical graphical user interface (GUI) programming concerns. As opposed to some other proposals available in the literature that indicate GUI programming concerns by simple intuition, we have conducted a systematic empirical analysis to derive our proposal. It included an analysis of an existing application programming interface (API), its use in industrial projects, and an analysis of the requirements and issues reported during software maintenance. In addition, we have evaluated more than 50 GUI frameworks and APIs and proved usefulness and generality of our classification of concerns. As an additional proof of applicability of the proposed classification, we have refactored the inheritance hierarchy of the selected GUI API using concern-oriented interfaces. We have implemented a supporting tool that complements the developed API and supports its concern-oriented use. The evaluation of the refactored API showed positive effects on API usability.     

Improving workflow modularity using a concern-specific layer on top of Unify

Workflows are a popular means of automating processes in many domains, ranging from high-level business process modeling to lower-level web service orchestration. However, state-of-the-art workflow languages offer a limited set of modularization mechanisms. This results in monolithic workflow specifications, in which different concerns are scattered across the workflow and tangled with one another. This hinders the design, evolution, and reusability of workflows expressed in these languages. We address this problem through the Unify framework. This framework enables uniform modularization of workflows by supporting the specification of all workflow concerns – including crosscutting ones – in isolation of each other. These independently specified workflow concerns are connected to each other using workflow-specific connectors. In order to further facilitate the development of workflows, we enable the definition of concern-specific languages (CSLs) on top of the Unify framework. A CSL facilitates the expression of a family of workflow concerns by offering abstractions that map well to the concerns' domain. Thus, domain experts can add concerns to a workflow using concern-specific language constructs. We exemplify the specification of a workflow in Unify, and show the definition and application of two concern-specific languages built on top of Unify.     

Fast Oxidative Removal of Refractory Aromatic Sulfur Compounds by a Magnetic Ionic Liquid

Magnetic ionic liquids (MIL) are extensively used in extraction and catalytic processes. Here, a series of MIL, i.e., 1‐n‐butyric acid‐3‐methylimidazolium chloride/xFeCl₃ ([C₃H₆COOHmim]Cl/xFeCl₃; x = 0.5, 1, 1.5, 2), were synthesized and characterized by infrared spectroscopy, visible absorption spectrometry, and electrospray ionization mass spectrometry. The MIL [C₃H₆COOHmim]Cl/2FeCl₃ was found to be highly active for the extraction and catalytic oxidative desulfurization of a model oil under mild conditions. Of note, the removal of benzothiophene, which has been regarded as a refractory aromatic sulfur compound, could be achieved at up to 100 % in 10 min. After reaction, the MIL could be easily separated from the model oil by applying an external magnetic field, due to its paramagnetic properties.     

Analytical Approach for Calculating the Separation Efficiency of Uniflow Cyclones

An approach for calculating the separation efficiency of uniflow cyclones for the separation of solid particles from gases is proposed. The analytical model is based on an equilibrium orbit concept, similar to that used in the Barth‐Muschelknautz model for conventional reverse‐flow cyclones, which has been proven to be successful for designing and calculating cyclones in a wide range of industrial applications. The proposed model takes into account the special flow pattern of uniflow cyclones, which differs substantially from that in reverse‐flow cyclones. The model provides correct dependencies of the separation efficiency on the main geometry and operation data of low‐loaded uniflow cyclones. Applying the calculation method to uniflow cyclones operated in test facilities indicates good agreement with experimental data.     

Behavior of Pieces of Plastic Sheet in Solid‐Liquid Fluidized Bed with Stirring

A solid‐liquid fluidized bed of inert particles can be used to separate pure objects from a mixture. Pieces of plastic sheet were selected as the objects to be separated. To estimate the separation characteristics, the behavior of pieces of plastic sheet in the bed was examined experimentally. Slow stirring was used to improve the fluidization state of the bed. The object size and the volume ratio of objects to inert particles were varied. The use of stirring of the bed was effective in improving the fluidization state of the bed, and the objects, which sank in the bed without stirring, moved from the bottom to the upper portion of the bed at a certain liquid velocity. This liquid velocity increases with decreasing object size, and it also increases as the volume ratio of objects to inert particles in the bed increases. When the volume ratio of objects to inert particles is too high, the objects are distributed throughout the entire bed, regardless of the liquid velocity.     

On the separation in 2-period double round robin tournaments with minimum breaks

This paper considers the separation in 2-period double round robin tournaments (2P-DRRTs) with minimum breaks. The separation is a lower bound on the number of slots between the two games with the same opponents. None of known schemes provides 2P-DRRTs with minimum breaks and a positive separation. We first propose a new scheme to generate 2-separation 2P-DRRTs with minimum breaks, based on single round robin tournaments (SRRTs) with minimum breaks which have the last break in the third slot from the end. Our experiment results show that such SRRTs exist for 8-68 teams. Secondly, we consider maximizing the separation in general 2P-DRRTs with minimum breaks by integer programming and constraint programming, respectively. The two approaches of direct formulation and “first-break, then-schedule” decomposition are presented and compared. We obtain the maximum separation for up to 14 teams. Furthermore, we consider the application with place constraints to show the flexibility and efficiency of scheduling 2P-DRRTs with minimum breaks and a positive separation.     

内蒙某铜钼矿石选矿试验研究

内蒙某铜钼矿石中金属矿物以为黄铁矿为主,其次为黄铜矿和辉钼矿等。辉钼矿粒度细小,各矿物共生关系密切而复杂,较难分离。采用阶段磨矿的混合浮选,混合精矿钼、铜、硫分离浮选工艺流程对该矿石进行选矿试验,获得了钼品位和钼回收率为46.30%和74.66%的钼精矿、铜品位和铜回收率为23.50%和70.16%的铜精矿以及硫品位和硫回收率为35.60%和79.55%的硫精矿。