Non-cyclic Processes Research Articles

Time has no dimensionality or physical existence

The author had been focusing on various treatments of time in physics for decades. The author felt that there were major shortcomings in the treatment of time in relativity and even in Newtonian physics. Then the author took a very pragmatic look at how time was actually treated in GPS to achieve a high precision, real world, working, physics system. The author thought that the actual GPS approach might yield a pragmatic time construct for physics. GPS does NOT use special relativity’s construct of time—but rather an observer independent construct as detailed below. The author put “Philosophical Time” musings aside and focused solely on finding the right physics construct for time. Finding that proper time was all that physics required, it dawned on the author, quite to his surprise, that proper time also met all the needs of philosophical time. Furthermore, an even deeper physics insight was that “proper time” is simply a measure of a stable physical process’ cycles. Hence, “time” as a separate physical entity disappeared to be replaced by physical processes each with its own idiosyncratic length/duration, all of which can be related to each other. These cyclic and noncyclic processes are all driven by known physical forces and energy sources. The properties of time, except for dimensionality, are actually just properties of each individual process that unfolds within 3D space and time is an emergent, human, generalization of process lengths.

Research of fault-tolerant control system of the formation process of carbon products

The production of carbon products is largely resource- and energy-intensive. That is why increasing the efficiency of this production is an urgent scientific and practical task, especially in modern conditions of constant growth of energy costs. An effective way to solve this problem is to create a modern process control system, taking into account the possible failures of system elements.
 The practice of operating hydraulic presses in carbon graphite production, the control valve of the hydraulic press sometimes fails or works with errors. That is why this paper considers the stage of loading the process of forming carbon products in terms of building a fault-tolerant pressing speed control system.
 The article investigates the fault-tolerant control system of carbon products, which is synthesized on the basis of traditional fault-tolerant systems for non-cyclic processes and control systems with iterative learning, which have demonstrated their effectiveness in control technological processes of cyclical nature. A method using linear matrix inequalities has been developed for optimal adjustment of control system parameters.
 Based on the combination of control with iterative learning and control that takes into account the failures of regulators, built a control system for the formation of carbon products, which takes into account both the cyclical nature of the technological process and possible failures of regulators. The research of the effectiveness of the control system by comparing its work with traditional fault-tolerant systems and control systems with iterative learning in the event of faults and disturbances of various kinds showed that the proposed system improves control quality not only over time during each cycle, but also from cycle to cycle.
 Further research should be aimed at the practical application of the proposed control system for different technological processes in different types of failures of regulatory bodies and the action of disturbances of different nature.

Fault-tolerant control system for the formation of carbon products

The production of carbon products is largely resource- and energy-intensive. That is why increasing the efficiency of this production is an urgent scientific and practical task, especially in modern conditions of constant growth of energy costs. An effective way to solve this problem is to create a modern process control system, taking into account possible failures of system components. A method for the synthesis of a fault-tolerant control system for the cyclic formation of carbon products has been developed, which takes into account control errors that are caused by malfunctions of controllers under conditions of unknown disturbances. According to the cyclic nature of the technological process under consideration, a control method with iterative learning was used in the synthesis of the control system. This method considers cyclic processes based on a two-dimensional model (2D model). The proposed control algorithm ensures the convergence of the control process with the task both in time and in each work cycle in order to promote the required quality of control even in the event of unknown disturbances and errors in the performance of controllers. The synthesis of the control system is based on the solution of a system of linear matrix inequalities. Based on the combination of a control method with iterative learning and a control method that takes into account failures in controllers, a method of constructing a fault-tolerant control system for the cyclic formation of carbon products has been synthesized to ensure acceptable operation of the control object in abnormal conditions. The control system has been synthesized by solving a system of linear matrix inequalities with the MATLAB software. In the future, it is necessary to consider optimal settings of the proposed control system and examine its effectiveness in comparison with conventional fault-tolerant systems for non-cyclic processes.

Performance evaluation, Optimization and exergy analysis of a high temperature co‐electrolysis power to gas process using Aspen Plus®‐a model based study

AbstractIn this paper, a high temperature coelectrolysis power to gas (LTE PtG) setup was developed that was fed a stereotypical feed in CO2 one could acquire from carbon capture and sequestration (CCS) retrofit. The electrolyzer was fed an equimolar 10 kmol/s feed in water and CO2 and the electrolyzer product was composed of 38.80 mole% CO2, 30.96 mole% CO, and 30.24 mole% H2 for a syngas conversion of 43.8%. The product from the methanation unit was only composed of 21.38 mole% CH4, with the rest (76.53 mole%) being predominantly CO2. The methanation unit was composed of only one Sabatier reactor operating at 313°C, which had 90% of its product recycled back to the front end of the unit. The electrolyzer was found to have a LHV efficiency of 31.49%, and the entire HTCE PtG process was found to have an efficiency of 74.31% with methane storage and 76.49% without methane storage. A novel adaptation was developed on previous work on the exergy analysis for flow‐sheet simulators which can be used for cyclic and noncyclic processes. The procedure was determined to be accurate, with irreversibilities determined across all the major subunits found to equal the irreversibility around the processes a whole. The electrolyzer was found to be responsible for the majority of the irreversibility within the setup, and this was attributed to the fact that water electrolysis is a very energy intensive process. The exergy efficiency of the electrolyzer was found to be 87.07% and that of the entire LTE PtG processes was found to be 84% with methane storage, and 87% without methane storage. In the end, it was determined that HTCE is unsuitable for the production of methane via retrofit with a methanation unit, and that it would be better suited for the production of liquid hydrocarbon fuels with much higher molecular carbon to hydrogen ratios.

Sensitivity of Numerical Weather Prediction to the Choice of Variable for Atmospheric Moisture Analysis into the Brazilian Global Model Data Assimilation System

Due to the high spatial and temporal variability of atmospheric water vapor associated with the deficient methodologies used in its quantification and the imperfect physics parameterizations incorporated in the models, there are significant uncertainties in characterizing the moisture field. The process responsible for incorporating the information provided by observation into the numerical weather prediction is denominated data assimilation. The best result in atmospheric moisture depend on the correct choice of the moisture control variable. Normalized relative humidity and pseudo-relative humidity are the variables usually used by the main weather prediction centers. The objective of this study is to assess the sensibility of the Center for Weather Forecast and Climate Studies to choose moisture control variable in the data assimilation scheme. Experiments using these variables are carried out. The results show that the pseudo-relative humidity improves the variables that depend on temperature values but damage the moisture field. The opposite results show when the simulation used the normalized relative humidity. These experiments suggest that the pseudo-relative humidity should be used in the cyclical process of data assimilation and the normalized relative humidity should be used in non-cyclic process (e.g., nowcasting application in high resolution).

Preface for Special Issue on Biology with X-ray Lasers 2.

In 1970, Breedlove and Tramel and later Solem and Baldwin (1982) suggested that the problem of radiation damage in structural biology might be solved by destroying the sample with a short pulse of intense radiation, because a few photons should be scattered before the onset of radiation damage. Following pioneering work by many, this outlandish idea is now a reality (see, e.g., Neutze et al., 2000; Gaffney and Chapman, 2007; Spence, 2008; Chapman et al., 2011; and Boutet et al., 2012)). This Special Issue, the proceedings of a meeting organized by the NSF Science & Technology Center for Biology with X-ray Lasers, constitutes a timely report on the latest developments, and a tantalizing view of what is yet to come. There has been progress on all fronts: instrumental, technical, and scientific. These developments have transformed heroic “campaigns” to focused experiments with acceptable requirements in beamtime and materials. Structure determinations, which in 2011 took 18 months from experiment to submitted paper, can now be completed in a few weeks, with a factor of 10 less beamtime, a factor of 4 less time for data analysis, and a factor of 100 less protein. Critical steps, such as de novo structure determination, have been demonstrated (Barends et al., 2014), and a wide variety of alternative approaches are under development (see this issue). The sheer range of systems shown to be amenable to Serial Femtosecond Crystallography has left little doubt about the validity of this approach, and its ability to deliver hitherto inaccessible insights into difficult systems and processes. The experimental and algorithmic methods developed for X-ray laser applications are increasingly migrating to synchrotrons. Recent experiments reported here also demonstrate the power of X-ray laser methods for time-resolved work, where the use of protein nanocrystals smaller than the optical absorption length of the pump light has produced the largest differences in a density map ever seen (Tenboer et al., 2014). Indeed, the “diffract-before-destroy” approach is now poised to extend serial femtosecond methods to non-cyclic processes, including enzymology, and sub-picosecond timescales inaccessible at synchrotrons. For longer times, mixing jets using nanocrystals smaller than diffusion lengths promise to allow diffusive mixing for the first time. More generally, the elucidation of femtosecond processes linking chemistry to biology is an enticing prospect under active investigation. The promise of determining structure without crystals has proved difficult to realize, but initial results are now emerging (Ekeberg et al., 2015), with more anticipated from an international collaboration involving many leading groups (Aquila et al., 2015). Recently, electron-based single-particle methods have begun to produce conformational movies and energy landscapes (Dashti et al., 2014) but remain constrained by the number of available snapshots. The X-ray laser has the capability to produce extremely large datasets under physiological conditions. As reported in this issue, it is imperative to develop means for compiling large datasets of useful snapshots obtained under tightly controlled and reproducible imaging conditions, and to correct any remaining imaging artifacts algorithmically. In a short time, the application of X-ray lasers to biology has moved from a debate on validity to a rapidly growing demonstration of unprecedented access to a treasure trove of new information. The reports in this Special Issue make it clear that the best is yet to come.

Tracking paleodeformation fields in the Mesozoic central Sierra Nevada arc: Implications for intra-arc cyclic deformation and arc tempos

In this study, structures in plutons and host rocks are coupled with geochronology to track paleodeformation fields from the late Paleozoic to Late Cretaceous in the central Sierra Nevada. Regional NW-striking host-rock foliation, NE- or SW-vergent thrust faults, and associated folds developed from the early Mesozoic to Early Cretaceous. Dextral transpressional shear zones developed in the Late Cretaceous. Strikes of steep-dipping magmatic foliations in Mesozoic plutons temporally vary from approximately NW (Triassic–Jurassic) to WNW (Late Cretaceous), displaying a progressive counterclockwise rotation. Joint interpretation based on combining host-rock and magmatic structures suggests that intra-arc paleodeformation fields were dominated by coaxial and arc-perpendicular contraction from the early Mesozoic to Early Cretaceous, becoming increasingly dextral transpressive in the Late Cretaceous. The switch from contraction to transpression was likely caused by oblique convergence between the Farallon and North American plates. Based on observations in the study area and other host-rock pendants in the central Sierra Nevada, we propose that the intensity of intra-arc deformation is cyclic. To some extent, it mimics the episodic pattern of arc magmatism: Stronger deformation coincides with magmatic flare-ups. Magmatism promotes intra-arc deformation, which in turn causes crustal thickening during transfer of materials downward to the magma source regions, potentially fertilizing source regions with supracrustal materials and resulting in increased magma generation. Thus, models addressing continental arc tempos should include intra-arc processes. Evolution of continental arcs may be influenced by linked cyclic processes within the arcs accompanied by noncyclic processes driven by events external to the arcs.

Modelling and Adaptive Control of Biochemical Processes

For a general dynamic biochemical process described by an ordinary differential equation, we introduce the concept of non-cyclic processes. This replaces the conservation of mass assumption and is sufficient to guarantee invariance of the positive orthant and boundedness of the trajectories. Non-cyclic processes are characterized in terms of the stoichiometric matrix and an algorithm is presented which decides in finitely many steps whether a process is non-cyclic or not. The concept of λ-tracking is applied to an example to regulate some external substrate concentration by the feedrate in the presence of noise corrupting the output and in the presence of input constraints.

Enhancement of Energy Conservation by Hill Reaction Inhibitors in Isolated Spinach(Spinacia oleracea)Chloroplast Fragments

The effect of diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], desmedipham [ethylm-hydroxycarbanilate carbanilate(ester)], propanil (3′,4′-dichloropropionanilide), and dibromothymoquinone (DBMIB) (2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone) on proton translocation and photophosphorylation in isolated spinach(Spinacia oleraceaL.) chloroplast fragments was investigated. In the absence of added cofactors, O2, or artificial electron acceptors, cyclic electron transport occurred, which was coupled to energy conservation. Under aerobic conditions O2acted as the terminal acceptor in non-cyclic electron transport. Proton translocation and photophosphorylation in the cyclic process were enhanced by diuron, desmedipham, and propanil, while in the non-cyclic process they were inhibited by all three herbicides. DBMIB inhibited proton translocation and photophosphorylation in both processes. Proton translocation and its enhancement increased with increasing light intensities. The finding that the plastoquinone (PQ) antagonist DBMIB disrupted cyclic as well as noncyclic electron flow, while diuron enhanced the cyclic and inhibited the noncyclic process, indicated that the acceptor site for endogenously-cycling electrons must lie between the active site of diuron inhibition and PQ, The close similarity in the behavior of diuron, desmedipham, and propanil suggests that their site of action is the same.

Glutamine Synthesis and Its Relation to Photophosphorylation in Pisum Chloroplasts

Illuminated pea (Pisum sativum) chloroplasts can convert glutamate to glutamine using ATP generated by photophosphorylation to drive the glutamine-synthetase reaction. Light-dependent glutamine synthesis is sensitive to 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU), but only at concentrations higher than are necessary to suppress photoreduction of ferricyanide or phosphoglycerate. Conversely, glutamine synthesis is far more sensitive to antimycin A than is photoconversion of phosphoglycerate to triosephosphate. When 3.8 mm phosphoglycerate is supplied, glutamine synthesis is stimulated in both the presence and absence of antimycin A.These data seem to be consistent with the operation of an endogenous, DCMU-sensitive, phosphorylation process-possibly cyclic-which can support glutamine synthesis in white light under aerobic conditions. The stimulatory effect of phosphoglycerate suggests that noncyclic phosphorylation is initiated or accelerated when this substrate is supplied. This noncyclic process evidently provides ATP over and above the amount required for phosphoglycerate photoreduction, i.e. the ATP/e(2) ratio exceeds 1.0. The additional ATP produced under these conditions is available for glutamine synthesis and lessens its dependence on cyclically (or pseudocyclically) generated ATP.

Oxygen dependency of in vivo photophosphorylation.

THE mechanism by which ATP is formed when the intact green is illuminated is not yet fully understood. ATP formation in isolated chloroplasts has been shown to be dependent on illumination1and has been shown to proceed by either a cyclic or a non-cyclic process depending on the oxido-reduction catalysts used2. Chloroplasts are capable of photophosphorylation at low rates in the absence of catalysts. This endogenous activity has been demonstrated to be oxygen dependent3,4. Ion-exchange chromatographic studies of the ATP content of intact barley seedlings show that the steady-state level of ATP in light is several fold that in dark5. The level with illumination drops if the leaves are exposed to nitrogen or to carbon monoxide–oxygen mixtures. This was interpreted as evidence that formation of ATP in barley seedlings in light was an oxidative process, using molecular oxygen as a terminal electron acceptor.