Design method for four-reflector type beam waveguide systems

Discussed is a method for the design of four reflector type beam waveguide feed systems, comprised of a conical horn and 4 focused reflectors, which are used widely as the primary reflector systems for communications satellite Earth station antennas. The design parameters for these systems are clarified, the relations between each parameter are brought out based on the beam mode development, and the independent design parameters are specified. The characteristics of these systems, namely spillover loss, crosspolarization components, and frequency characteristics, and their relation to the design parameters, are also shown. It is also indicated that design parameters which decide the dimensions of the conical horn or the shape of the focused reflectors can be unerringly established once the design standard for the system has been selected as either: (1) minimizing the crosspolarization component by keeping the spillover loss to within acceptable limits, or (2) minimizing the spillover loss by maintaining the crossover components below an acceptable level and the independent design parameters, such as the respective sizes of the focused reflectors and the distances between the focussed reflectors, etc., have been established according to mechanical restrictions. A sample design is also shown. In addition to being able to clarify the effects of each of the design parameters on the system and improving insight into these systems, the efficiency of these systems will also be increased with this design method

Vergleichende Untersuchung der curareartig wirkenden Gifte am Skelettmuskel

Es wurden an den isolierten Gastroknemien der Esculenten die Wirkungen vieler curareartig wirkender Gifte mit einander verglichen, nachdem sie in der Giftlösung 1.5 Stunden lang gelegen hatten. Eine Gruppe der Gifte, wie Guanidin, Adrenalin, Tyramin und Kalium, zeigt in Dosen, die kleiner sind als die lähmenden, eine erregende Wirkung auf die motorischen Nervenendigungen. Unter Giften, die vor der totalen Lähmung der Nervenendigungen den Muskel angreifen, unterscheidet man eine Gruppe, die auf den Muskel erst erregend wirken, und eine andere, die auf ihn nur eine lähmende Wirkung ausüben. Zur ersteren gehören Brucin, Strychinin, Guanidin, Atropin, Tetraäthylammonium und Campher, und zur letzteren gehören Acetylcholin, Tetramethylammonium, Atophan, Natriumsalicylat und Thebain. Nach der Grösse des Abstandes von den nervenlähmenden Konzentrationen bis den muskellähmenden, also nach der Grösse der Wirkungszone der curareartigen Wirkung, ordnen sich die geprüften Gifte in der folgenden Reihe: Tetramethylammonium > Brucin > Strychinin > Acetylcholin > Guanidin > Tetrodotoxin > Adrenalin > Atropin > Tyramin, Kalium, Tetraäthylammonium > Natriumsalicylat, Thebain, Atophan. (Das Nikotin scheint nach dem Versuche von Okushima, nächst dem Tetramethylammonium zu stehen)

Development of a data set of pesticide dissipation rates in/on various plant matrices for the Pesticide Properties Database

© 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).Data relating to the rate at which pesticide active substances dissipate on or within various plant matrices are important for a range of different risk assessments including those related to occupational exposure and consumer safety. However, despite the importance of this data, dissipation rates, often expressed as the pesticide half-life, are not included in the most common online data resources. Databases have been collated in the past but these tend not to be maintained or regularly updated. The purpose of the exercise described herein was to collate a new database in a format compatible with the main online pesticide database resource (the Pesticide Properties Database, PPDB), to validate this database in line with the Pesticide Properties Database protocols and thus ensure that the data is maintained and updated in future. The outcome of the study is a database based on data collated from 1390 published articles covering over 400 pesticides and over 200 crops across a wide variety of different matrices (leaves, fruits, seeds etc.) for pesticide residues on the crop surface as well as residues absorbed within the plant material. This data is now fully incorporated into the PPDB.Peer reviewe

Efficient Implementation of Genus Three Hyperelliptic Curve Cryptography over GF(2^n)

The optimization of the Harley algorithm is an active area of hyperelliptic curve cryptography. We propose an efficient method for software implementation of genus three Harley algorithm over GF(2^n). Our method is based on fast finite field multiplication using one SIMD operation, SSE2 on Pentium 4, and parallelized Harley algorithm. We demonstrated that software implementation using proposed method is about 11% faster than conventional implementation

2,4-Dichloro­benzaldehyde

In the crystal structure of the title compound, C7H4Cl2O, the mol­ecules form a network of weak C—H⋯O inter­actions involving the aldehyde O atom and the ortho-H atom on the benzene ring together with C—H⋯O inter­actions between the formyl groups. Together, these connect the mol­ecules into (10) layers, which are stabilized additionally by π–π stacking inter­actions of the benzene rings [centroid–centroid distance = 3.772 (1) Å]. The aldehyde group is twisted relative to the benzene ring by 7.94 (13)°