Suspended sediment in lowland rivers – towards identifying the ratios of mineral and organic components and their variation during the year

Concentrations of suspended sediment transported by rivers are influenced by interactions between multiple drivers that act on a range of spatial and temporal scales. Such levels vary over the year, as well as across multi-year periods. Most conventional approaches to determining suspended load are based upon analyses of total suspended sediment concentration (SSC), i.e., the sum of mineral and organic matter. This approach makes it difficult, if not impossible, to determine the impact of multiple environmental factors on changes in suspension concentration precisely. The present paper focuses on the mineral and organic components of suspended sediment with the aim of determining how our knowledge of the share of each individual component can improve interpretations of SSC fluctuations during a hydro-logical year. The analysis conducted (personal and other researchers’ results) has shown that mineral and organic suspensions demonstrate mutually incompatible opposite trends under influence of environmental factors. This analysis of organic components identifies clear seasonal trends, which indicates that organic suspensions of autogenous origin have a strong influence on the dynamics of changes in suspension concentration; such analyses are rarely included in assessments of SSC dynamics.

Simple spectrophotometric methods for the determination of amlodipine and atorvastatin in bulk and tablets

Background Simultaneous spectrophotometric determination of samples containing more than one analyte presents analytical challenge; the choice of an analytical procedure is strictly related to the extent of overlapping between the individual absorption peaks of these components; if the absorption peaks are satisfactorily resolved, the determination is not problematic, but if the individual component signals are partly or totally overlapped, then powerful techniques are needed. Combined amlodipine and atorvastatin are typical example where special techniques are needed to resolve bands overlapping. Results Application of multiwavelength regression and absorbance factor methods to the analysis of atorvastatin and amlodipine combination proved to be satisfactorily capable of accurate and precise determination of the two analytes. The two methods recoveries were very close to the expected analytes concentrations, and the precision of the methods was < 2% relative standard deviation. Statistical comparison indicated that there is no significant difference between the assay results obtained by the two method as the calculated t values 0.91 and 1.13 for amlodipine and atorvastatin, respectively, were less than the tabulated t value 2.23 at 95% confidence level. Conclusion The proposed methods are accurate, precise, simple and inexpensive. They can be applied successfully to the analysis of the two drugs in combined dosage form.

Intelligent Pitch Controller Identification and Design

This paper exhibits a comparative assessmentbased on time response specification performance between modern and classical controller for a pitch control system of an aircraft system. The dynamic modeling of pitch control system is considered on the design of an autopilot that controls the pitch angle It starts with a derivation of a suitable mathematical model to describe the dynamics of an aircraft. For getting close to actual conditionsthe white noise disturbance is applied to the system.In this paper it is assumed that the modelpitch control systemis not available. So using the identification system and Box-Jenkins model estimator we identify the pitch control system System’s identification is a procedure for accurately characterizing the dynamic response behavior of a complete aircraft, of a subsystem, or of an individual component from measureddata.To study the effectiveness of the controllers, the LQR Controller and PID Controller and fuzzy controller is developed for controlling the pitch angle of an aircraft system. Simulation results for the response of pitch controller are presented instep’s response. Finally, the performances of pitch control systems are investigated and analyzed based on common criteria of step’s response in order to identify which control strategy delivers better performance with respect to the desired pitch angle. It is found from simulation, that the fuzzy controller gives the best performance compared to PID and LQR controller.

Recent Advances in the Catalytic Treatment of Volatile Organic Compounds: A Review Based on the Mixture Effect

Catalytic total oxidation is an efficient technique for treating VOCs, which are mainly emitted by solvent-based industrial processes. However, studies of the catalytic oxidation of VOCs in combination with other pollutants are very limited, despite the fact that this is a key step of knowledge before industrial application. During the oxidation reaction, the behavior of a molecule may change depending on the reaction mixture. For the treatment of an effluent loaded with VOCs, it is necessary to carefully select not only the catalytic material to be used but also the reaction conditions. Indeed, the catalytic oxidation of a component in a VOCs mixture is not predicted solely from the behavior of individual component. Thus, the objective of this small review is to carry out a study on the effect observed in the case of the oxidation of a VOCs mixture or in the presence of water, NOX or sulfur compounds.

Differences in finished case quality between Invisalign and traditional fixed appliances:

ABSTRACT Objectives To compare the treatment and posttreatment effects of Invisalign aligners that incorporated SmartForce features and attachments to traditional fixed appliances. Materials and Methods This randomized controlled trial included 66 patients, 32 aligners, and 34 fixed-appliance patients. The median ages of the aligner and braces patients were 26.7 (interquartile range [IQR]: 9.8) and 25.9 (IQR: 16.6) years, respectively. Pretreatment occlusion was assessed using the ABO Discrepancy Index. Posttreatment (T1) and 6-month retention (T2) occlusions were quantified using the ABO Objective Grading System (OGS) scores. Results The braces group finished treatment significantly (P &lt; .001) earlier (0.4 years) than the aligner group. The median DI scores for the aligner and braces groups were 4.5 and 7.0, respectively, which was a statistically significant (P = .015), but clinically insignificant, difference. There were no statistically significant between-group differences for the total OGS scores or any of the individual component scores at debond (T1) or after 6 months of retention (T2). During the posttreatment period, alignment and overjet worsened significantly in the aligner group, while buccolingual inclinations and occlusal relations improved. Over the same period, alignment worsened in the braces group and buccolingual inclinations improved. There was no statistically significant between-group difference in posttreatment changes of the total OGS scores. Conclusions While patients with simple malocclusions require 4.8 months longer treatment times with aligners than traditional braces, the treatment and 6-month posttreatment occlusal outcomes are similar.

The Most Discriminant Components of Force Platform Data for Gait Based Person Re-identification

Walking gait data measured using force platforms is a promising means for person re-identification in authentication and surveillance scenarios. We aimed to determine the most discriminant components of force platform data using a two-stream Convolutional Recurrent Neural Network (KineticNet). Each network in the two-stream architecture extracts features pertaining to a single stance phase and then these features are fused to represent the entire gait cycle. Over two sessions, ground reaction forces (Fx, Fy, Fz), moments (Mx, My, Mz), and center of pressure coordinates (Cx, Cy) were acquired from 118 participants as they walked our laboratory five times at preferred speed. For each participant and each session, up to three samples were reserved for network training, leaving one sample for network validation and one sample for network testing. KineticNet’s performance was evaluated using both individual component and multi-component inputs before ablation studies were conducted on its architecture. Fz was the most discriminant individual component, and re-identification using Fz, Fy, and Cy together was the most accurate overall at 96.02%. These results warrant further investigation into the utility of force platforms as an accessory or alternative to video cameras for gait based person re-identification.

The Most Discriminant Components of Force Platform Data for Gait Based Person Re-identification

Walking gait data measured using force platforms is a promising means for person re-identification in authentication and surveillance scenarios. We aimed to determine the most discriminant components of force platform data using a two-stream Convolutional Recurrent Neural Network (KineticNet). Each network in the two-stream architecture extracts features pertaining to a single stance phase and then these features are fused to represent the entire gait cycle. Over two sessions, ground reaction forces (Fx, Fy, Fz), moments (Mx, My, Mz), and center of pressure coordinates (Cx, Cy) were acquired from 118 participants as they walked our laboratory five times at preferred speed. For each participant and each session, up to three samples were reserved for network training, leaving one sample for network validation and one sample for network testing. KineticNet’s performance was evaluated using both individual component and multi-component inputs before ablation studies were conducted on its architecture. Fz was the most discriminant individual component, and re-identification using Fz, Fy, and Cy together was the most accurate overall at 96.02%. These results warrant further investigation into the utility of force platforms as an accessory or alternative to video cameras for gait based person re-identification.

Synergistic effect between flake graphite and small-sized graphene in lithium storage

As anode material for lithium-ion batteries, graphite has the disadvantage of relatively low specific capacity. In this work, a simple yet effective strategy to overcome the disadvantages by using a composite of flake graphite (FG) and small-sized graphene (SG) has been developed. The FG/SG composite prepared by dispersing FG and SG (90:10 w/w) in ethanol and drying delivers much higher specific capacity than that of individual component except for improved rate capability. More surprisingly, FG/SG composite delivers higher reversible capacity than its theoretical value calculated according to the theoretical capacities of graphite and graphene. Therefore, a synergistic effect between FG and SG in lithium storage is clearly discovered. To explain it, we propose a model that abundant nanoscopic cavities were formed due to physical adhesion between FG and SG and could accommodate extra lithium.

A Mini-review on Ultra Performance Liquid Chromatography

Chromatography is a widely used analytical tool for separating a mixture of compounds into individual component. High performance liquid chromatography (HPLC) is one of the most important methods used for the separation, identification and quantification of a compounds present in a mixture. It meets many criteria of analysis but its main drawbacks are it is relatively time consuming to run a chromatogram and consumes high amount of solvent compared to other analytical methods. There is a need to develop a method which can overcome these drawbacks of HPLC. Ultra performance liquid chromatography (UPLC) is the new approach which opens novel direction in the field of liquid chromatography. It works on similar principle but shows better performance than conventional HPLC. UPLC is a technique of liquid chromatography with improved runtime and sensitivity with less than 2 μm particle size. The UPLC separation process is carried out under very high pressure (up to100 MPa). Additionally, it reduces the cost of reagent with shorter run time as compared to conventional HPLC. This article updated until 2020, provides a general review on the principle, instrumentation and application of UPLC in different fields of science.