scholarly journals Natural microbial polysaccharides as effective factors for modification of the catalytic properties of fungal cellobiose dehydrogenase

2021 ◽  
Author(s):  
Justyna Sulej ◽  
Magdalena Jaszek ◽  
Monika Osińska-Jaroszuk ◽  
Anna Matuszewska ◽  
Renata Bancerz ◽  
...  
Keyword(s):  
Catalytic Properties ◽  
Cellobiose Dehydrogenase ◽  
Pycnoporus Sanguineus ◽  
Practical Applications ◽  
Control Value ◽  
Electrochemical Parameters ◽  
Optimum Ph ◽  
Stabilization Effect ◽  
Fungal Polysaccharides ◽  
The Stability

AbstractPolysaccharides are biopolymers composed of simple sugars like glucose, galactose, mannose, fructose, etc. The major natural sources for the production of polysaccharides include plants and microorganisms. In the present work, four bacterial and two fungal polysaccharides (PS or EPS) were used for the modification and preservation of Pycnoporus sanguineus cellobiose dehydrogenase (CDH) activity. It was found that the presence of polysaccharide preparations clearly enhanced the stability of cellobiose dehydrogenase compared to the control value (4 °C). The highest stabilization effect was observed for CDH modified with Rh110EPS. Changes in the optimum pH in the samples of CDH incubated with the chosen polysaccharide modifiers were evidenced as well. The most significant effect was observed for Rh24EPS and Cu139PS (pH 3.5). Cyclic voltammetry used for the analysis of electrochemical parameters of modified CDH showed the highest peak values after 30 days of incubation with polysaccharides at 4 °C. In summary, natural polysaccharides seem to be an effective biotechnological tool for the modification of CDH activity to increase the possibilities of its practical applications in many fields of industry.

scholarly journals Direct Z-scheme GdFeO3/g-C3N4 heterostructures with outstanding photocatalytic activity

2021 ◽  
Author(s):  
Li Li ◽  
Fengwu Wang ◽  
Jiajun Feng ◽  
Siqi Guo ◽  
Mai Xu ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Organic Pollutants ◽  
Recombination Rate ◽  
Catalytic Properties ◽  
Photocatalytic Property ◽  
Practical Applications ◽  
Ultrasonic Synthesis ◽  
Visible Light Driven ◽  
The Stability ◽  
Synthesis Approach

Abstract The direct Z-scheme GdFeO3/g-C3N4 photocatalysts used without any mediators were obtained using an ultrasonic synthesis approach. The composites’ structures, elemental composition and morphologies, as well as optical, electrochemical and catalytic properties, were thoroughly analyzed. GdFeO3/g-C3N4-3:7 composite exhibited an excellent enhanced light-harvesting ability and low recombination rate, which manifested into an outstanding visible-light driven activity, 7.7 and 2.3 times more than of stand-alone g-C3N4 and GdFeO3, respectively. A mechanism responsible for the photocatalytic property enhancement was proposed. The stability and reusability of the GdFeO3/g-C3N4 composites make them excellent materials for practical applications related to the removal of organic pollutants from the wastewater.

scholarly journals STUDIES ON THE FUNCTION OF INTRACELLULAR RIBONUCLEASES

1966 ◽  
Vol 29 (3) ◽  
pp. 395-403 ◽  
Author(s):  
Takeshi Utsunomiya ◽  
Jay S. Roth
Keyword(s):  
Natural Products ◽  
Sodium Chloride ◽  
Rat Liver ◽  
Messenger Rna ◽  
Rnase Activity ◽  
Optimum Ph ◽  
Normal Rat ◽  
Pancreatic Rnase ◽  
The Stability ◽  
Normal Constituent

The RNase activity and properties of ribosome and polysome preparations from normal rat liver and some hepatomas have been examined. Polysome and ribosome preparations from the Novikoff, McCoy MDAB, and Dunning hepatomas had considerably higher specific RNase activity than corresponding preparations from normal rat liver, Novikoff ascites, or Morris 5123 hepatomas. The optimum pH of the RNase was approximately 8.5 for all samples tested, and the samples showed no evidence of latent RNase activity when treated with 3 M sodium chloride, EDTA, urea, or p-chloromercuribenzenesulfonic acid. The RNase activity appeared to be associated principally with breakdown products and/or subunits smaller than 80S. In the presence of Mg++ ions, subunits could reaggregate to form monomer ribosomes indistinguishable from the natural products, but some of the reassociated ribosomes could contain RNase activity which had been bound to the smaller particles. Similar results were obtained with spermine. In the hepatomas, evidence was obtained for the preexistence of considerable amounts of the smaller, RNase-containing subunits in the cell. When a small amount of crystalline bovine pancreatic RNase was added to partly dissociated ribosomes, the RNase was found only in association with the smaller subunits, and little or no enzyme was taken up by ribosomes or polysomes. The results have led to the conclusion that RNase is not a normal constituent of the ribosome or polysome, but that RNase may become associated with these particulates if dissociation and reassociation take place. Some implications of these findings for the stability of messenger RNA and for the mechanism of its breakdown are discussed.

Non-adhesive lotus and other hydrophobic materials

2008 ◽  
Vol 366 (1870) ◽  
pp. 1539-1556 ◽  
Author(s):  
David Quéré ◽  
Mathilde Reyssat
Keyword(s):  
Solid Surface ◽  
Room Temperature ◽  
Water Repellency ◽  
Short Review ◽  
Water Repellent ◽  
Practical Applications ◽  
Hydrophobic Materials ◽  
Volatile Liquid ◽  
Air Cushion ◽  
The Stability

Superhydrophobic materials recently attracted a lot of attention, owing to the potential practical applications of such surfaces—they literally repel water, which hardly sticks to them, bounces off after an impact and slips on them. In this short review, we describe how water repellency arises from the presence of hydrophobic microstructures at the solid surface. A drop deposited on such a substrate can float above the textures, mimicking at room temperature what happens on very hot plates; then, a vapour layer comes between the solid and the volatile liquid, as described long ago by Leidenfrost. We present several examples of superhydrophobic materials (either natural or synthetic), and stress more particularly the stability of the air cushion—the liquid could also penetrate the textures, inducing a very different wetting state, much more sticky, due to the possibility of pinning on the numerous defects. This description allows us to discuss (in quite a preliminary way) the optimal design to be given to a solid surface to make it robustly water repellent.

Effect of the ionizing radiation on the catalytic activity of the BASF K-3-10 catalyst in the low-temperature conversion of carbon monoxide by water vapour. Stability of the radiation catalytic effects

1986 ◽  
Vol 51 (8) ◽  
pp. 1571-1578 ◽  
Author(s):  
Alois Motl
Keyword(s):  
Carbon Monoxide ◽  
Catalytic Activity ◽  
Low Temperature ◽  
Catalytic Effect ◽  
Catalytic Properties ◽  
Beta Radiation ◽  
Fast Neutrons ◽  
Time Interval ◽  
The Stability ◽  
Catalytic Effects

The radiation catalytic properties of the BASF K-3-10 catalyst were studied, namely the dependence of these effects on the time interval between the catalyst irradiation and the reaction itself and also on the length of the catalyst use. The catalytic effects decrease exponentially with the interval between the irradiation and the reaction if the catalyst is kept in the presence of air. The stability of effects induced by various types of radiations increases in the sequence beta radiation - gamma radiation - fast neutrons. The radiation catalytic effect stability in the reaction increases in the same sequence.

A Taxonomy to Aid in the Design of Complex Physical Activities for Older Adults

2017 ◽  
Vol 61 (1) ◽  
pp. 21-25
Author(s):  
Lyndsie M. Koon ◽  
Robert J. Brustad ◽  
Megan Babkes Stellino
Keyword(s):  
Physical Activity ◽  
Older Adults ◽  
Cognitive Function ◽  
Environmental Context ◽  
Physical Activities ◽  
The Body ◽  
Practical Applications ◽  
Aging Adults ◽  
The Stability ◽  
Positive Results

Physical activity participation is a non-pharmaceutical intervention that can be utilized to maintain and improve cognitive function in aging adults. Although simple physical activities yield positive results in regards to cognitive function, cognitively and motorically complex physical activities may have an even greater benefit on neuroplasticity for older adults. Commercially available products such as physical activity apps or exergames offer this population a means to engage in regular physical activity on their own. However, a taxonomy is necessary to help distinguish simpler physical activities from more complex physical activities. The taxonomy proposed in this paper carefully considers the following characteristics: the stability or transport of the body, object manipulation, intertrial variability, the environmental context and the reaction or to others. The dimensions of the taxonomy are operationally defined and practical applications are provided.

Stability characteristics of lubricating film in mill oil-film bearings

2018 ◽  
Vol 70 (1) ◽  
pp. 201-211 ◽  
Author(s):  
Jianmei Wang ◽  
Zhixiong Li ◽  
Sadoughi Mohammadkazem ◽  
Min Cai ◽  
Jianfeng Kang ◽  
...  
Keyword(s):  
Influential Factors ◽  
Film Stability ◽  
High Rotational Speed ◽  
Content Type ◽  
Oil Film ◽  
Practical Applications ◽  
Lubricating Film ◽  
Operation Conditions ◽  
Comparison Results ◽  
The Stability

Purpose The stability characteristics of an oil film directly influence the safety and service life of mill oil-film bearings. However, very limited work has been done to address the stability characteristics of mill oil-film bearings. To this end, this paper aims to investigate the stability characteristics of mill oil-film bearings through theoretical and experimental analysis. Design/methodology/approach For the first time, a special designed experiment platform was developed to investigate the stability characteristics of mill oil-film bearings. In addition, a theoretical model of lubricating film of the tested bearings was established to analyze the oil-film stability. The theoretical results were compared with the experimental results. Findings The comparison results demonstrate that the critical influential factors on the bearing stability were the eccentricity ratio and the ratio of bearing length to diameter. The mill bearing was likely to be unstable under a small load and at a high rotational speed. Practical implications The paper includes implications for suitable operation conditions in practical use of mill oil-film bearings. Originality/value This paper fulfills an identified need to investigate oil-film stability of mill bearings for practical applications.

scholarly journals Variable Structure Compensation PID Control of Asymmetrical Hydraulic Cylinder Trajectory Tracking

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Difei Liu ◽  
Zhiyong Tang ◽  
Zhongcai Pei
Keyword(s):  
Trajectory Tracking ◽  
Pid Control ◽  
Control Method ◽  
Sliding Mode ◽  
Variable Structure ◽  
Hydraulic Cylinder ◽  
Control Value ◽  
Equivalent Control ◽  
Asymmetrical Hydraulic Cylinder ◽  
The Stability

A novel variable structure compensation PID control, VSCPID in short, is proposed for trajectory tracking of asymmetrical hydraulic cylinder systems. This new control method improves the system robustness by adding a variable structure compensation term to the conventional PID control. The variable structure term is designed according to sliding mode control method and therefore could compensate the disturbance and uncertainty. Meanwhile, the proposed control method avoids the requirements for exact knowledge of the systems associated with equivalent control value in SMC that means the controller is simple and easy to design. The stability analysis of this approach is conducted with Lyapunov function, and the global stability condition applied to choose control parameters is provided. Simulation results show the VSCPID control can achieve good tracking performances and high robustness compared with the other control methods under the uncertainties and varying load conditions.

Biquadratic Digital Phase-Compensator Design with Stability-Margin Controllability

2019 ◽  
Vol 28 (04) ◽  
pp. 1950068 ◽  
Author(s):  
Tian-Bo Deng
Keyword(s):  
Stability Margin ◽  
Transformation Method ◽  
Second Order ◽  
Approximation Accuracy ◽  
Parameter Transformation ◽  
Practical Applications ◽  
Compensator Design ◽  
Novel Method ◽  
Design Idea ◽  
The Stability

This paper proposes a novel method for the design of a recursive second-order (biquadratic) all-pass phase compensator with controllable stability margin. The design idea stems from the generalized stability triangle (GST) derived by the author for the second-order biquadratic digital filter. Based on the GST, a parameter-transformation method is proposed on the transformations of the denominator coefficients of the transfer function of the biquadratic phase compensator. The transformations convert the original denominator coefficients to other new parameters, and any values of those new parameters can guarantee that the GST condition is always satisfied. Optimizing the new parameters yields a biquadratic phase compensator that definitely meets a prespecified stability margin. That is, a biquadratic all-pass phase compensator can be designed to have an arbitrarily specified stability margin. This in turn avoids the occurrence that a recursive phase compensator may become unstable in the practical applications. Thus, the resulting biquadratic phase compensator has robust stability, which is extremely important during the practical filtering operations. A design example is given to show the stability margin guarantee as well as the approximation accuracy.

Is There a Relation Between Synchronization Stability and Bifurcation Type?

2020 ◽  
Vol 30 (08) ◽  
pp. 2050123
Author(s):  
Zahra Faghani ◽  
Zhen Wang ◽  
Fatemeh Parastesh ◽  
Sajad Jafari ◽  
Matjaž Perc
Keyword(s):  
Complex Networks ◽  
Nonlinear Dynamical Systems ◽  
General Relation ◽  
Dynamical Behavior ◽  
Stability Function ◽  
Nonlinear Dynamical ◽  
Practical Applications ◽  
Stability Functions ◽  
Stability And Bifurcation ◽  
The Stability

Synchronization in complex networks is an evergreen subject with many practical applications across the natural and social sciences. The stability of synchronization is thereby crucial for determining whether the dynamical behavior is stable or not. The master stability function is commonly used to that effect. In this paper, we study whether there is a relation between the stability of synchronization and the proximity to certain bifurcation types. We consider four different nonlinear dynamical systems, and we determine their master stability functions in dependence on key bifurcation parameters. We also calculate the corresponding bifurcation diagrams. By means of systematic comparisons, we show that, although there are some variations in the master stability functions in dependence on bifurcation proximity and type, there is in fact no general relation between synchronization stability and bifurcation type. This has important implication for the restrained generalizability of findings concerning synchronization in complex networks for one type of node dynamics to others.

scholarly journals Adsorption Behavior and Electron Structure Engineering of Pd-Based Catalysts for Acetylene Hydrochlorination

Catalysts ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 24 ◽  
Author(s):  
Yaqing Cen ◽  
Yuxue Yue ◽  
Saisai Wang ◽  
Jinyue Lu ◽  
Bolin Wang ◽  
...  
Keyword(s):  
Palladium Catalysts ◽  
Influence Factor ◽  
Catalytic Performance ◽  
Electron Structure ◽  
Acetylene Hydrochlorination ◽  
Practical Applications ◽  
Highly Active ◽  
New Strategy ◽  
Function Relationship ◽  
The Stability

Adsorption and activation for substrates and the stability of Pd species in Pd-based catalysts are imperative for their wider adoption in industrial and practical applications. However, the influence factor of these aspects has remained unclear. This indicates a need to understand the various perceptions of the structure–function relationship that exists between microstructure and catalytic performance. Herein, we revisit the catalytic performance of supported-ionic-liquid-phase stabilized Pd-based catalysts with nitrogen-containing ligands as a promoter for acetylene hydrochlorination, and try to figure out their regulation. We found that the absolute value of the differential energy, |Eads(C2H2)-Eads(HCl)|, is negative correlated with the stability of palladium catalysts. These findings imply that the optimization of the electron structure provides a new strategy for designing highly active yet durable Pd-based catalysts.

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