Cryptanalysis of two mutual authentication protocols for low-cost RFID

Radio Frequency Identification (RFID) is appearing as a favorite technology for automated identification, which can be widely applied to many applications such as e-passport, supply chain management and ticketing. However, researchers have found many security and privacy problems along RFID technology. In recent years, many researchers are interested in RFID authentication protocols and their security flaws. In this paper, we analyze two of the newest RFID authentication protocols which proposed by Fu et al. and Li et al. from several security viewpoints. We present different attacks such as desynchronization attack and privacy analysis over these protocols.Comment: 17 pages, 2 figures, 1 table, International Journal of Distributed and Parallel system

Growing up in the Iran-Iraq war and preferences for strong defense

The purpose of this study is to examine the relationship between individuals’ experiences of the Iran–Iraq war (1980–1988) during early adulthood (18–25 years) and their preference for strong national defense forces and their willingness to fight for Iran (in the event of another war). Using the World Values Survey data, we provide evidence that Iranians who experienced the war during their early adulthood give top priority to strong defense forces. However, we find that there is no significant association between individuals’ experiences of the war during early adulthood and their willingness to fight for Iran. The results are robust to controlling for a set of individuals’ socioeconomic and political characteristics as well as different age cohorts. Finally, we show that our results are not influenced by age cohort effect

P–C and C–H Bond Cleavages of dppm in the Thermal Reaction of [Ru\u3csub\u3e3\u3c/sub\u3e(CO)\u3csub\u3e10\u3c/sub\u3e(μ-dppm)] with Benzothiophene: X-ray structures of [Ru\u3csub\u3e6\u3c/sub\u3e(μ-CO)(CO)\u3csub\u3e13\u3c/sub\u3e{μ\u3csub\u3e4\u3c/sub\u3e-PhP(C\u3csub\u3e6\u3c/sub\u3eH\u3csub\u3e4\u3c/sub\u3e)PPh}(μ\u3csub\u3e6\u3c/sub\u3e-C)] and [Ru\u3csub\u3e4\u3c/sub\u3e(CO)\u3csub\u3e9\u3c/sub\u3e(μ\u3csub\u3e3\u3c/sub\u3e-η\u3csup\u3e2\u3c/sup\u3e-PhPCH\u3csub\u3e2\u3c/sub\u3ePPh\u3csub\u3e2\u3c/sub\u3e)(μ\u3csub\u3e4\u3c/sub\u3e-η\u3csup\u3e6\u3c/sup\u3e:η\u3csup\u3e1\u3c/sup\u3e:η\u3csup\u3e1\u3c/sup\u3e-C\u3csub\u3e6\u3c/sub\u3eH\u3csub\u3e4\u3c/sub\u3e)(μ-H)]

The thermal reaction of [Ru3(CO)10(μ-dppm)] (1) with benzothiophene in refluxing toluene gives a complex mixture of products. These include the known compounds [Ru2(CO)6{μ-CH2PPh(C6H4)PPh}] (2), [Ru2(CO)6{μ-C6H4PPh(CH2)PPh}] (3), [Ru3(CO)9{μ3-η3-(Ph)PCH2P(Ph)C6H4}] (4) and [Ru3(CO)10{μ-η2-PPh(CH2)(C6H4)PPh}] (6), as well as the new clusters [Ru6(μ-CO)(CO)13{μ3-η2-PhP(C6H4)PPh}(μ6-C)] (5) and [Ru4(CO)9(μ3-η2-PhPCH2PPh2)(μ4-η6:η1:η1-C6H4)(μ-H)] (7). The solid-state molecular structures of 5 and 7 were confirmed by single crystal X-ray analyses. Compound 5 consists of interesting example of a hexaruthenium interstitial carbido cluster having a tetradentate diphosphine ligand derived from the activation of P–C and C–H bonds of the dppm ligand in 1. The tetranuclear compound 7 consists of a unique example of a non-planar spiked triangular metal fragment of ruthenium [Ru(1), Ru(2) and Ru(3)] unit with Ru(4) being bonded to Ru(1). The μ4-η1:η6:η1-benzyne ligand in this compound represents a previously uncharacterized bonding mode for benzyne. Compounds 5 and 7 do not contain any benzothiophene-derived ligand. The reaction of 4 with benzothiophene gives 2, 3, 5 and 6. Thermolysis of 1 in refluxing toluene gives 2, 3 and 4; none of 5 and 7 is detected in reaction mixture

Ruthenium and osmium carbonyl clusters incorporating stannylene and stannyl ligands

The reaction of [Ru₃ (CO)₁₂] with Ph₃SnSPh in refluxing benzene furnished the bimetallic Ru-Sn compound [Ru₃(CO)₈(μ-SPh)₂(μ3-SnPh₂)(SnPh₃)₂] 1 which consists of a SnPh₂ stannylene bonded to three Ru atoms to give a planar tetra-metal core, with two peripheral SnPh₃ ligands. The stannylene ligand forms a very short bond to one Ru atom [Sn-Ru 2.538(1) Å] and very long bonds to the other two [Sn-Ru 3.074(1) Å]. The germanium compound [Ru₃(CO)₈(μ-SPh)₂(μ₃-GePh₂)(GePh₃)₂] 2 was obtained from the reaction of [Ru₃ (CO)₁₂] with Ph₃GeSPh and has a similar structure to that of 1 as evidenced by spectroscopic data. Treatment of [Os₃(CO)₁₀(MeCN)₂] with Ph₃SnSPh in refluxing benzene yielded the bimetallic Os-Sn compound [Os₃(CO)₉(μ-SPh)(μ₃-SnPh₂)(MeCN)(ƞ¹-C₆H₅)] 3. Cluster 3 has a superficially similar planar metal core, but with a different bonding mode with respect to that of 1. The Ph₂Sn group is bonded most closely to Os(2) and Os(3) [2.7862(3) and 2.7476(3) Å respectively] with a significantly longer bond to Os(1), 2.9981(3) Å indicating a weak back-donation to the Sn. The reaction of the bridging dppm compound [Ru₃(CO)₁₀(μ-dppm)] with Ph₃SnSPh afforded [Ru₃(CO)₆(μ-dppm)(μ₃-S)(μ₃-SPh)(SnPh₃)] 5. Compound 5 contains an open triangle of Ru atoms simultaneously capped by a sulfido and a PhS ligand on opposite sides of the cluster with a dppm ligand bridging one of the Ru-Ru edges and a Ph₃Sn group occupying an axial position on the Ru atom not bridged by the dppm ligand

Globalization and the outbreak of COVID-19 : an empirical analysis

The purpose of this study is to examine the relationship between the extension of globalization and coronavirus disease 2019 (COVID-19) case fatality rate (CFR) calculated on 28 July 2020 in more than 150 countries. Our regression analyses show that countries with higher levels of socio-economic globalization are exposed to higher levels of CFR. The positive association between the level of globalization of countries and their COVID-19 fatality rate remains robust, controlling for cross-country differences in economic development and demographics, health care costs, health care capacity, quality of governance and continental dummies

Evaluation of Bond Strength Between Carbon Fiber Reinforced Polymer (CFRP) Composites with Modified Epoxy Resins and Concrete

Rehabilitation and strengthening of concrete structures are becoming more significant in civil engineering applications. The use of externally bonded Fiber Reinforced Polymers (FRP) is one of the methods to strengthen and rehabilitate reinforced concrete members, providing noticeable improvement to their capacity in resisting load. Carbon Fiber Reinforced Polymer (CFRP) is used along with epoxy resins to evaluate the bond strength of two commercially available epoxies (EPON 828 and EPON 862) between CFRP and concrete. In addition, three new combinations that resulted from mixing the two epoxies were examined. The mechanical properties of epoxy resins are significantly weaker than this of the CFRP making the epoxy characteristics the determining factor in the quality of the bond strength. Three-point flexural test was conducted to examine the bond strength between the CFRP composites and concrete. Further, differential scanning calorimetry was conducted to examine the glass transition temperature of the resultant epoxies. The results showed that the optimum composition was a mixture of 70% of epoxy 828 and 30% of epoxy 862. Therefore, achieving better bond strength and high glass transition temperature, resulting in CFRP composite with higher fire resistance

Dirhenium Carbonyl Complexes Bearing 2-Vinylpyridine, Morpholine and 1-Methylimidazole Ligands

Treatment of the labile compound [Re2(CO)8(MeCN)2] with 2-vinylpyridine in refluxing benzene affords exclusively the new compound [Re2(CO)8(μ-η1:η2-NC5H4CHCH2)] (1) in 39% yield in which the μ-η1:η2-vinylpyridine ligand is coordinated to one Re atom through the nitrogen and to the other Re atom via the olefinic double bond. Reaction of [Re2(CO)8(MeCN)2] with morpholine in refluxing benzene furnishes two compounds, [Re2(CO)9(η1-NC4H9O)] (2) and [Re2(CO)8(η1-NC4H9O)2] (3) in 5% and 29% yields, respectively. Reaction of [Re2(CO)8(MeCN)2] with 1-methylimidazole gives [Re2(CO)8{η1-NC3H3N(CH3)}2] (4) and the mononuclear compound fac-[ReCl(CO)3{η1-NC3H3N(CH3)}2] (5) in 18% and 26% yields, respectively. In the disubstituted compounds 2 and 4, the heterocyclic ligands occupy equatorial coordination sites. The mononuclear compound 5 consists of three CO groups, two N coordinated η1-1-methylimidazole ligands and a terminal Cl ligand. The XRD structures of complexes 1, 3 and 5 are reported

An electron-deficient triosmium cluster containing the thianthrene ligand: Synthesis, structure and reactivity of [Os₃(CO)₉(μ3-η2-C₁₂H₇S₂)(μ-H)]

Reaction of [Os₃(CO)₁₀(CH₃CN)₂] with thianthrene at 80 °C leads to the nonacarbonyl dihydride compound [Os₃(CO)₉(μ-3,4-η²-C₁₂H₆S₂)(μ-H)₂] (1) and the 46-electron monohydride compound [Os₃(CO)₉(μ₃-η²-C₁₂H₇S₂)(μ-H)] (2). Compound 2 reacts reversibly with CO to give the CO adduct [Os₃(CO)₁₀(μ-η²-C₁₂H₇S₂)(μ-H)] (3) whereas with PPh₃ it gives the addition product [Os₃(CO)₉)(PPh₃)(μ-η²-C₁₂H₇S₂)(μ-H)] (4) as well as the substitution product 1,2-[Os₃(CO)₁₀ ((PPh₃)₂] (5) Compound 2 represents a unique example of an electron-deficient triosmium cluster in which the thianthrene ring is bound to cluster by coordination of the sulfur lone pair and a three-center-two-electron bond with the C(2) carbon which bridges the same edge of the triangle as the hydride. Electrochemical and DFT studies which elucidate the electronic properties of 2 are reported

Double Carbon−Hydrogen Activation of 2-Vinylpyridine: Synthesis of Tri- and Pentanuclear Clusters Containing the μ-NC\u3csub\u3e5\u3c/sub\u3eH\u3csub\u3e4\u3c/sub\u3eCH═C Ligand

Reactions of 2-vinylpyridine with the triruthenium complexes [Ru3(CO)12] and [Ru3(CO)10(μ-dppm)] leads to a previously unknown double carbon−hydrogen bond activation of the β-carbon of the vinyl group to afford the pentaruthenium and triruthenium complexes [Ru5(CO)14(μ4-C5H4CH═C)(μ-H)2] (1) and [Ru3Cl(CO)5(μ-CO)(μ-dppm)(μ3-NC5H4CH═C)(μ-H)] (2), respectively. Crystal structures reveal two different forms of bridging of the dimetalated 2-vinylpyridyl ligand, capping a square face in 1 and a triangular face in 2