Critical discussion of the determination of internal losses in state-of-the-art (Al,In)GaN laser diodes

2020 ◽  
Author(s):  
Dominic J. Kunzmann ◽  
Raphael Kohlstedt ◽  
Tino Uhlig ◽  
Ulrich T. Schwarz
Keyword(s):  
State Of The Art ◽  
Laser Diodes ◽  
Critical Discussion

scholarly journals The Degree of Oxidation of Graphene Oxide

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 560
Author(s):  
Alexandra Carvalho ◽  
Mariana C. F. Costa ◽  
Valeria S. Marangoni ◽  
Pei Rou Ng ◽  
Thi Le Hang Nguyen ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Ab Initio ◽  
State Of The Art ◽  
High Accuracy ◽  
Precise Determination ◽  
Photoemission Spectroscopy ◽  
Pristine Graphene ◽  
X Ray ◽  
Degree Of Oxidation

We show that the degree of oxidation of graphene oxide (GO) can be obtained by using a combination of state-of-the-art ab initio computational modeling and X-ray photoemission spectroscopy (XPS). We show that the shift of the XPS C1s peak relative to pristine graphene, ΔEC1s, can be described with high accuracy by ΔEC1s=A(cO−cl)2+E0, where c0 is the oxygen concentration, A=52.3 eV, cl=0.122, and E0=1.22 eV. Our results demonstrate a precise determination of the oxygen content of GO samples.

scholarly journals Characterization and Quantification of Selenoprotein P: Challenges to Mass Spectrometry

2021 ◽  
Vol 22 (12) ◽  
pp. 6283
Author(s):  
Jérémy Lamarche ◽  
Luisa Ronga ◽  
Joanna Szpunar ◽  
Ryszard Lobinski
Keyword(s):  
Mass Spectrometry ◽  
State Of The Art ◽  
Animal Health ◽  
Primary Standard ◽  
Selenoprotein P ◽  
Primary Standards ◽  
Analytical Approaches ◽  
Careful Investigation ◽  
Accurate Quantification

Selenoprotein P (SELENOP) is an emerging marker of the nutritional status of selenium and of various diseases, however, its chemical characteristics still need to be investigated and methods for its accurate quantitation improved. SELENOP is unique among selenoproteins, as it contains multiple genetically encoded SeCys residues, whereas all the other characterized selenoproteins contain just one. SELENOP occurs in the form of multiple isoforms, truncated species and post-translationally modified variants which are relatively poorly characterized. The accurate quantification of SELENOP is contingent on the availability of specific primary standards and reference methods. Before recombinant SELENOP becomes available to be used as a primary standard, careful investigation of the characteristics of the SELENOP measured by electrospray MS and strict control of the recoveries at the various steps of the analytical procedures are strongly recommended. This review critically discusses the state-of-the-art of analytical approaches to the characterization and quantification of SELENOP. While immunoassays remain the standard for the determination of human and animal health status, because of their speed and simplicity, mass spectrometry techniques offer many attractive and complementary features that are highlighted and critically evaluated.

Problem of angular motion control of a non-cooperative on-orbit service object

2021 ◽  
Vol 2021 (1) ◽  
pp. 37-50
Author(s):  
A.A. Fokov ◽  
◽  
O.P. Savchuk ◽  
Keyword(s):  
Motion Control ◽  
State Of The Art ◽  
Object Motion ◽  
The State ◽  
Angular Motion ◽  
Motion Parameter ◽  
Rotary Motion ◽  
Parameter Determination ◽  
Service Object

The realization of existing projects of on-orbit servicing and the development of new ones is a steady trend in the development of space technology. In many cases, on-orbit service clients are objects that exhibit an undesired rotary motion, which renders their servicing difficult or impossible. The problem of on-orbit service object motion control determines the topicality of studies aimed not only at the refinement of methods and algorithms of controlling both the translational and the rotary motion of an object, but also at the development and refinement of methods of onboard determination of the object – service spacecraft relative motion parameters. This paper overviews the state of the art of the problem of object motion parameter determination in on-orbit servicing tasks and existing methods of object motion control and angular motion damping and specifies lines of further investigations into the angular motion control of non-cooperative service objects. Based on the analysis of publications on the subject, the applicability of onboard means for object motion parameter determination is characterized. The analysis of the applicability of methods of remote determination of the parameters of an unknown non-cooperative object from a service spacecraft shows that they are at the research stage. The input data for the verification of methods proposed in the literature were simulated or taken from ground experiments or previous missions. Contact and contactless methods of angular motion control of non-cooperative on-orbit service objects are considered. From the state of the art of investigations into the contactless motion control of on-orbit service objects it may be concluded that the most advanced contactless method of motion control of an on-orbit service object is a technology based on the use of an ion beam directed to the object from an electrojet engine onboard a service spacecraft. Lines of further investigations into non-cooperative object motion control are proposed.

N and P on-line meters: requirements, maintenance and stability

1996 ◽  
Vol 33 (1) ◽  
pp. 147-157 ◽  
Author(s):  
Henrik A. Thomsen ◽  
Kenneth Kisbye
Keyword(s):  
Sample Preparation ◽  
Response Time ◽  
Ammonium Nitrate ◽  
State Of The Art ◽  
List Price ◽  
User Friendliness ◽  
On Line ◽  
The Cost ◽  
Preparation Design

State-of-the-art on-line meters for determination of ammonium, nitrate and phosphate are presented. The on-line meters employ different measuring principles and are available in many different designs differing with respect to size, calibration and cleaning principle, user-friendliness, response time, reagent and sample consumption. A study of Danish experiences on several plants has been conducted. The list price of an on-line meter is between USD 8000 and USD 35,000. To this should be added the cost of sample preparation, design, installation and running-in. The yearly operating for one meter are in the range of USD 200-2500 and the manpower consumption is in the range of 1-5 hours/month. The accuracy obtained is only slightly smaller than the accuracy on collaborative laboratory analyses, which is sufficient for most control purposes.

scholarly journals Determination of the composition of multilayer plastic packaging with NIR spectroscopy

Detritus ◽  
2020 ◽  
pp. 62-66
Author(s):  
Xiaozheng Chen ◽  
Nils Kroell ◽  
Alexander Feil ◽  
Thomas Pretz
Keyword(s):  
Infrared Spectroscopy ◽  
Near Infrared ◽  
State Of The Art ◽  
Nir Spectroscopy ◽  
Waste Recycling ◽  
Point Of View ◽  
Plastic Packaging ◽  
Post Industrial ◽  
Detection And Separation

In food and medical packaging, multiple layers of different polymers are combined in order to achieve optimal functional properties for various applications. Flexible multilayer plastic packaging achieves a reduction in weight compared to other packaging products with the same function, saving material and in transportation costs. Recycling of post-industrial multilayer packaging was achieved by some companies, but the available technologies are limited to specific polymer types. For post-consumer waste, recycling of multilayer packaging has not been achieved yet. One of the main challenges in plastic sorting is that the detection and separation of multilayer packaging from other materials is not possible yet. In this study, the possibility to detect and sort flexible multilayer plastic packaging was investigated with near-infrared spectroscopy, which is the state-of-the-art technology for plastic sorting. The results show that from a detection and classification point of view, sorting of monolayer, two- and three-layers samples under laboratory conditions is possible. According to the captured data, the sequence of layers has little influence on the spectra. In case of glossy samples, the spectra are influenced by printed surfaces. With an increase in thickness, the spectra get more characteristic, which makes the classification easier. Our results indicate that the sorting of post-consumer multilayer plastic packaging by main composition is theoretically achievable.

scholarly journals Kertsopoulos Innovation: The Three Multi-plane Polarities and the Three Interactions and Schematic Representations in the Sense of the General Cause of the Dynamic Difference

2019 ◽  
Vol 3 (1) ◽  
Keyword(s):  
Magnetic Fields ◽  
Magnetic System ◽  
State Of The Art ◽  
Magnetic Devices ◽  
Know How ◽  
Patented Invention ◽  
Scientific Laws ◽  
First Time ◽  
Multiple Interactions

As it is known: in the state of the art, the like and the unlike polarity between two magnets remains independent of the distance between them. According to the invention: “Magnetic System of Three Interactions”, International office of patents WIPO-PCT, bearing the No WO/2013/136097of the inventor Georgios K. Kertsopoulos, the like and the unlike polarity between two magnetic constructions depends on the distance between them [1], [2], [3], [4], [5], [6], [7], [8], [9], [10]. The know-how of the invention makes it possible for interacting magnetic constructions to possess and perform interchangeable more than 96 polarities and interactions. Polarities and magnetic fields can in multiple ways interchange, depending on the varying distance between two interacting confronted magnetic constructions, offering many new variable design capabilities. For the first time, new types of poles are created, for example: simultaneous like-unlike poles or simultaneous unlike-like poles are created, causing stable or unstable balance as an interaction; also, for the first time in magnetism, new types of magnetic fields are formed never before observed, for example: remote fields of very strong attraction, without however, the contact of the magnetic constructions. The magnetic devices that perform these multiple interactions are fully patented internationally, published in a book in English, by the inventor a book in English, by the inventor [11]. The new scientific laws and principles, revealed through these experiments enrich the very basics, the foundation of magnetism, since many new types of polarities and interactions are introduced and are made possible for the first time in science and technology. In figure 1 of the article we observe the division and determination of the empty air space, between the magnetic constructions, at three distances and two boundaries which apply both for the like and the unlike front poles and in figure 2 we observe the three typical spatial distances, the three multi-plane polarities and the three interactions with properties and with spatial boundaries and interactions based on the bundles of the dynamic lines between the two magnetic constructions, on the guide, when the poles of the front poles of the arrangements are initially like. Furthermore, in figure 7 we observe a schematic representation of the three different fields (175), (177) and (178) between the above-mentioned magnetic arrangements of the constructions of the invention, with initially like front poles, in the sense of the general cause of the dynamic difference. This article is in continuation of the following published article that introduces the reader to the invention’s technology: Georgios K. Kertsopoulos (2018) Innovation article: 36 over passed restrictions of magnetism achieved by the 96 multiple magnetic polarities-interactions performed by the Kertsopoulos world patented invention vs. the known two. Advances in Nanoscience and nanotechnology [12]. https://www.opastonline.com/wp-content/uploads/2018/12/36-over-passed-restrictions-of-magnetism-achieved-by-the-96- multiple-magnetic-polarities-interactions-performed-by-the-kertsopoulos-world-ann-18.pdf?fbclid=IwAR1jYPFME5mhX2FLbKKTPAdu0YMe3FqHtoUdoRoeao8mKIp1GRuWeovEaA

scholarly journals Application of Monte Carlo Methods to Consider Probabilistic Effects in a Race Simulation for Circuit Motorsport

2020 ◽  
Vol 10 (12) ◽  
pp. 4229 ◽  
Author(s):  
Alexander Heilmeier ◽  
Michael Graf ◽  
Johannes Betz ◽  
Markus Lienkamp
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Monte Carlo Method ◽  
State Of The Art ◽  
Probability Distributions ◽  
Strategic Decisions ◽  
The Monte Carlo Method ◽  
Random Events ◽  
Example Variability

Applying an optimal race strategy is a decisive factor in achieving the best possible result in a motorsport race. This mainly implies timing the pit stops perfectly and choosing the optimal tire compounds. Strategy engineers use race simulations to assess the effects of different strategic decisions (e.g., early vs. late pit stop) on the race result before and during a race. However, in reality, races rarely run as planned and are often decided by random events, for example, accidents that cause safety car phases. Besides, the course of a race is affected by many smaller probabilistic influences, for example, variability in the lap times. Consequently, these events and influences should be modeled within the race simulation if real races are to be simulated, and a robust race strategy is to be determined. Therefore, this paper presents how state of the art and new approaches can be combined to modeling the most important probabilistic influences on motorsport races—accidents and failures, full course yellow and safety car phases, the drivers’ starting performance, and variability in lap times and pit stop durations. The modeling is done using customized probability distributions as well as a novel “ghost” car approach, which allows the realistic consideration of the effect of safety cars within the race simulation. The interaction of all influences is evaluated based on the Monte Carlo method. The results demonstrate the validity of the models and show how Monte Carlo simulation enables assessing the robustness of race strategies. Knowing the robustness improves the basis for a reasonable determination of race strategies by strategy engineers.

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