Role of compositional changes on thermal,magnetic,and mechanical properties of Fe-P-C-based amorphous alloys

This work aimed to tune the comprehensive properties of Fe-P-C-based amorphous system through investigating the role of microalloying process on the crystallization behavior,glass forming ability(GFA),soft magnetic features,and mechanical properties.Considering minor addition of elements into the system,it was found that the simultaneous microalloying of Ni and Co leads to the highest GFA,which was due to the optimization of compositional heterogeneity and creation of near-eutectic composition.Moreover,the FeCoNiCuPC amorphous alloy exhibited the best anelastic/viscoplastic behavior under the nanoindentation test,which was owing to the intensified structural fluctuations in the system.However,the improved plasticity by the extra Cu addition comes at the expense of magnetic properties,so that the saturation magnetization of this alloying system is significantly decreased compared to the FeCoPC amorphous alloy with the highest soft magnetic properties.In total,the results indicated that a combination of added elemental constitutes,i.e.,Fe69Co5Ni5Cu1P13C7 composition,provides an optimized state for the comprehensive properties in the alloying system.     

UV-activated multilayer nanomatrix provides one-step tunable carbohydrate structural characterization in MALDI-MS

The structure-specific fragmentation of gas-phase ions in tandem mass spectrometry among other techniques provides an efficient analytical method for confirming unknown analytes or for elucidating chemical structures. Using concentration-dependent UV-absorbing matrix-functionalized magnetic nanoparticles and matrix-assisted laser desorption-ionization mass spectrometry (MALDI MS), we developed a single-step pseudo-MS/MS approach for tunable ionization and fragmentation to facilitate structure determination. Without chemical derivatization, we have demonstrated that this approach successfully distinguished isomeric sets of di-, tri- and tetrasaccharides. Low concentration of nanomatrix provided an enhanced signal for accurate mass determination of the intact molecular ions of analytes present in the sample. In contrast, high concentration of nanomatrix induced extensive and unique fragmentation, including high-energy facile bond breakage (A- and X-type cross-ring cleavages), which facilitated the linkage and sequence characterization of oligosaccharides without conventional tandem mass spectrometric instrumentation. The practicality of this approach for complex sample analysis was evaluated by an oligosaccharide mixture, wherein molecular ions are unambiguously observed and signature product ions are distinguishable enough for molecular identification and isomer differentiation by this simple tunable approach. By probing the roles of the multilayer nanomatrix components: matrix (energy absorption), silane-coating (energy pooling and dissipation) and core Fe₃O₄ (fragmentation), a plausible energy transfer mechanism was proposed based on a computational study and photoelectron experiments. The differentiation of tri- and tetra-oligosaccharide shown in this study not only demonstrated the first step toward glycan characterization by nanoparticle-assisted MALDI-MS, but also shed some insight on the nanoparticle-mediated energy transfer dynamics behind our approach.     

On Coprime Modules and Comodules

Many observations about coalgebras were inspired by comparable situations for algebras. Despite the prominent role of prime algebras, the theory of a corresponding notion for coalgebras was not well understood so far. Coalgebras C over fields may be called coprime provided the dual algebra C* is prime. This definition, however, is not intrinsic—it strongly depends on the base ring being a field. The purpose of the article is to provide a better understanding of related notions for coalgebras over commutative rings by employing traditional methods from (co)module theory, in particular (pre)torsion theory.

Dualizing classical primeness condition, coprimeness can be defined for modules and algebras. These notions are developed for modules and then applied to comodules. We consider prime and coprime, fully prime and fully coprime, strongly prime and strongly coprime modules and comodules. In particular, we obtain various characterisations of prime and coprime coalgebras over rings and fields.     

An optical fiber biosensor for chlorpyrifos using a single sol-gel film containing acetylcholinesterase and bromothymol blue

An optical fiber biosensor consisting of acetylcholinesterase (AChE) and bromothymol blue (BTB) doped sol-gel film was employed to detect organophosphate pesticide chlorpyrifos. The main advantage of this optical biosensor is the use of a single sol-gel film with immobilized AChE and BTB. The compatibility of this mixture (AChE and BTB) with the sol-gel matrix has prevented leaching of the film. The immobilization of the enzyme and indicator was simple without chemical modification. The biosensing element on single sol-gel film has been placed inside the flow-cell for flow system. In the presence of a constant AChE, a color change of the BTB and the measured reflected signal at wavelength 622nm could be related to the pesticide concentration in the sample solutions. The performance of optical biosensor in the flow system has been optimized, including chemical and physical parameters. The response time of the biosensor is 8min. A linear calibration curve of chlorpyrifos against the percentage inhibition of AChE was obtained from 0.05 to 2.0mg/L of chlorpyrifos (18-80% inhibition, R(2)=0.9869, n=6). The detection limit for chlorpyrifos was 0.04mg/L. The results of the analysis of 0.5-1.5mg/L of chlorpyrifos using this optical biosensor agreed well with chromatographic method.     

Current Research of Phytochemical,Medicinal and Non-Medicinal Uses of Uncaria gambir Roxb.: A Review

Uncaria gambir Roxb. is a plant from Southeast Asia and is widely used as an alternative medicine with various applications. This plant has been widely used in traditional medicine. This paper aims to provide information on U. gambir, a summary of data on phytochemicals and on medical and nonmedical activities. Phytochemical studies reveal biologically active constituents such as flavonoids, phenolics, and alkaloids. Various studies have shown that extracts and compounds obtained from U. gambir have medical uses for their antioxidant, antibacterial, anti-helminthic, anticancer, antifungal, anti-inflammatory, anti-hyperglycemic, anti-hyperuricemic, anti-lipid peroxidation, antihyperlipidemic and other properties. In addition, this extract has other uses, such as adsorbent for dyes and metal ions, as well as corrosion inhibition. Thus, U. gambir, which is commonly used in traditional medicine, is a potential plant for many therapeutic applications and prospects for drug development as well as other applications such as adsorbent and corrosion inhibition.