A Modal Series Representation of Genesio Chaotic System

In this paper an analytic approach is devised to represent, and study the behavior of, nonlinear dynamic chaotic Genesio system using general nonlinear modal representation. In this approach, the original nonlinear ordinary differential equations (ODEs) of model transforms to a sequence of linear time- invariant ODEs. By solving the proposed linear ODEs sequence, the exact solution of the original nonlinear problem is determined in terms of uniformly convergent series. Also an efficient algorithm with low computational complexity and high accuracy is presented to find the approximate solution. Simulation results indicate the effectiveness of the proposed method.Comment: International Journal of Instrumentation and Control Systems (IJICS) Vol.2, No.3, July 201

Cheyletid mites associated with stored rice in Iran; the first record of Chelacheles strabismus from Iran and a key for their identification

طی سال‌های 1386-1385 بررسی در خصوص شناسایی کنه‌های انباری برنج در استان گیلان انجام شد. در این بررسی شش گونه از کنه‌های خانواده‌ی Cheyletidae (Acari: Prostigmata) شاملCheletomorpha lepidopterorum ، Acaropsellina sollers،Chelacheles strabismus ،Cheyletus eruditus ،Cheyletus carnifex و Cheyletus malaccensis جمع‌آوری و شناسایی شدند. گونه‌ی Chelacheles strabismus Baker برای اولین‌بار از ایران گزارش می‌شود. کلیدی برای شناسایی گونه‌های کنه‌های خانواده Cheyletidae موجود در انبارهای برنج ارائه شده است

First report of two species of predatory mites (Acari: Phytoseiidae) for Iranian fauna

During 2005-2006, an investigation was carried out on the mites associated with stored rice in Guilan province, Iran. Two species of Phytoseiid mites were collected and identified as Proprioseiopsis bregetovae (Abbasova, 1970) and Typhlodromus (Anthoseius) transvaalensis (Nesbitt, 1951). Both are reported here for the first time from Iran. The association of these two species with the habitat of stored rice is also new

Catalytic cleavage of HEAT and subsequent covalent binding of the tetralone moiety by the SARS-CoV-2 main protease

Here we present the crystal structure of SARS-CoV-2 main protease (Mpro) covalently bound to 2-methyl-1-tetralone. This complex was obtained by co-crystallization of Mpro with HEAT (2-(((4-hydroxyphenethyl)amino)methyl)-3,4-dihydronaphthalen-1(2H)-one) in the framework of a large X-ray crystallographic screening project of Mpro against a drug repurposing library, consisting of 5632 approved drugs or compounds in clinical phase trials. Further investigations showed that HEAT is cleaved by Mpro in an E1cB-like reaction mechanism into 2-methylene-1-tetralone and tyramine. The catalytic Cys145 subsequently binds covalently in a Michael addition to the methylene carbon atom of 2-methylene-1-tetralone. According to this postulated model HEAT is acting in a pro-drug-like fashion. It is metabolized by Mpro, followed by covalent binding of one metabolite to the active site. The structure of the covalent adduct elucidated in this study opens up a new path for developing non-peptidic inhibitors

Response of free-standing graphene monolayer exposed to ultrashort intense XUV pulse from free-electron laser

The response of a free-standing graphene monolayer exposed to a few tens of femtoseconds long extreme ultraviolet (XUV) pulse was studied theoretically in order to analyze and compare contributions of various mechanisms to the graphene damage, understood here as a global atomic disintegration. Our simulation results indicate that nonthermal disintegration of the atomic structure is the predominant damage mechanism for a free-standing graphene layer. Only at high absorbed doses, charge-induced disintegration of the graphene structure prevails. We also demonstrate that the progressing damage can be probed by femtosecond optical pulses in the soft UV regime (4 eV photon energy). The achieved quantitative understanding of the damage mechanisms may enable a better control of graphene-based devices when they are exposed to x-ray radiation, as well as an efficient processing of graphene layers with ultrashort intense XUV pulses

Response of free-standing graphene monolayer exposed to ultrashort intense XUV pulse from free-electron laser

The response of a free-standing graphene monolayer exposed to a few tens of femtoseconds long extreme ultraviolet (XUV) pulse was studied theoretically in order to analyze and compare contributions of various mechanisms to the graphene damage, understood here as a global atomic disintegration. Our simulation results indicate that nonthermal disintegration of the atomic structure is the predominant damage mechanism for a free-standing graphene layer. Only at high absorbed doses, charge-induced disintegration of the graphene structure prevails. We also demonstrate that the progressing damage can be probed by femtosecond optical pulses in the soft UV regime (4 eV photon energy). The achieved quantitative understanding of the damage mechanisms may enable a better control of graphene-based devices when they are exposed to x-ray radiation, as well as an efficient processing of graphene layers with ultrashort intense XUV pulses

Effect of Cr on the hydrogen storage and electronic properties of BCC alloys: Experimental and first-principles study

Inventing an effective method to store large amounts of hydrogen at room temperature is one of the key challenges in developing a hydrogen-based economy. Metal hydrides have attracted attention owing to their promising hydrogen storage capabilities. We have systematically studied the structural and electronic properties of mechanically synthesized Ti0.5V1.5-xCrx (0 ≤ x ≤ 0.3) alloys and investigated the influence of the addition of Cr atoms on the hydrogen storage properties of vanadium-rich body-centered-cubic (V-BCC) alloys. X-ray diffraction (XRD) results indicate that all alloys are composed of BCC main phase, with the lattice parameters exhibiting no change following chemical modification. The kinetic measurements have revealed that Cr-containing alloys exhibit improved hydrogen uptake. X-ray photoelectron spectroscopy (XPS) measurements have shown that the addition of Cr has a significant effect on the anti-oxidation properties of V-BCC alloys, increasing their chemical activity and thus enhancing the hydrogen storage properties. Moreover, XPS results elucidate the role of activation of the studied materials. Additionally, the electrochemical properties of the negative electrodes (as part of Ni-MHx secondary batteries) made of Ti0.5V1.4-xNi0.1Crx (0 ≤ x ≤ 0.3) system have been studied by cyclic charge-discharge and demonstrate that doping of the V-BCC alloys with Cr can significantly improve the cycle-life stability of anode that exhibits similar discharge performance up to 50 cycles. First principles simulations are used to analyse the changes in the electronic density of states close to the Fermi level, as a function of Cr concentration, as well as binding energies and structural changes upon hydrogen absorption. Furthermore, ab initio studies confirmed that H absorption is favoured with increasing Cr-content. Our study highlights the importance of the addition of Cr to V-BCC alloys on both solid-gas and electrochemical hydrogenation reactions.Financial assistance from National Science Centre, Poland (no. 2015/17/N/ST8/00271). This project has received funding from the EU-H2020 research and innovation programme under grant agreement No 654360 having benefitted from the access provided by Mateusz Balcerzak in DESY NanoLab (Hamburg, Germany) and ICN2 (Barcelona, Spain) within the framework of the NFFA-Europe Transnational Access Activity. M. Pruneda acknowledges financial support from Spanish MICIU, AEI, and EU FEDER (Grant No. PGC2018-096955-B-C43) and Generalitat de Catalunya (Grant No. 2017SGR1506).Peer reviewe