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51.
SS Kapoor 《Pramana》2002,59(6):941-950
In this talk we present an overview of accelerator-driven sub-critical reactor systems (ADS), and bring out their attractive features for the elimination of troublesome long-lived components of the spent fuel, as well as for nuclear energy generation utilizing thorium as fuel. In India, there is an interest in the programmes of development of high-energy and high-current accelerators due to the potential of ADS in utilizing the vast resources of thorium in the country for nuclear power generation. The accelerator related activities planned in this direction will be outlined.  相似文献   
52.
We demonstrated the application of a simple electrode geometry for dielectrophoresis (DEP) on colloidal probes as a form of molecular force spectroscopy in a highly parallel format. The electric field between parallel plates is perturbed with dielectric microstructures, generating uniform DEP forces on colloidal probes in the range of several hundred piconewtons across a macroscopic sample area. We determined the approximate crossover frequency between negative and positive DEP using electrodes without dielectric microstructures-a simplification over standard experimental methods involving quadrupoles or optical trapping. 2D and 3D simulations of the electric field distributions validated the experimental behavior of several of our DEP tweezers geometries and provided insight into potential improvements. We applied the DEP tweezers to the stretching of a short DNA oligomer and detected its extension using total-internal reflection fluorescence microscopy. The combination of a simple cell fabrication, a uniform distribution of high axial forces, and a facile optical detection of our DEP tweezers makes this form of molecular force spectroscopy ideal for highly parallel detection of stretching or unbinding kinetics of biomolecules.  相似文献   
53.
Standard Model extensions often predict low‐mass and very weakly interacting particles, such as the axion. A number of small‐scale experiments at the intensity/precision frontier are actively searching for these elusive particles, complementing searches for physics beyond the Standard Model at colliders. Whilst a next generation of experiments will give access to a huge unexplored parameter space, a discovery would have a tremendous impact on our understanding of fundamental physics.  相似文献   
54.
In this study, donor–acceptor random polymers containing benzotriazole acceptor and bistriphenylamine and benzodithiophene donors, P1 and P2 , were successfully synthesized by Stille coupling polymerization. The effect of bistriphenylamine moiety and thiophene π‐conjugated linker on electrochemical, spectroelectrochemical, and optical behaviors of the polymers were investigated. Optoelectronic properties and photovoltaic performance of the polymers were examined under the illumination of AM 1.5G, 100 mW cm?2. The polymers were characterized by cyclic voltammetry, UV‐Vis‐NIR absorption spectroscopy, gel permeation chromatography. HOMO/LUMO energy levels of P1 and P2 were calculated as ?5.47 eV/–3.41 eV and ?5.43 eV/–3.27 eV, respectively. Bulk heterojunction type solar cells were constructed using blends of the polymers (donor) and [6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) (acceptor). Photovoltaic studies showed that the highest power conversion efficiency of these photovoltaic devices were recorded as 3.50% with open circuit voltage; 0.79 V, short circuit current; 9.45 mA cm?2, fill factor; 0.53 for P1 :PC71BM (1:2, w/w) in 3% o‐dichlorobenzene (o‐DCB) solution and 3.15% with open circuit voltage; 0.75 V, short circuit current; 8.59 mA cm?2, fill factor; 0.49 for P2 :PC71BM (1:2, w/w) in 2% chlorobenzene (CB) solution. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 3705–3715  相似文献   
55.
Modeling and control of vehicle suspension system are high noteworthy from safety to comfort. In this paper, an analytical nonlinear half-vehicle model which is included quadratic tire stiffness, cubic suspension stiffness, and coulomb friction is derived based on fundamental physics. A hybrid fuzzy logic approach which combines fuzzy logic and PID controllers is designed for reducing the vibration levels of passenger seat and vehicle body. Performances of designed controllers have been evaluated by numerical simulations. Comparisons with classical PID control, Fuzzy Logic Control (FLC) and Hybrid Fuzzy-PID control (HFPID) have also been provided. Results of numerical simulations are evaluated in terms of time histories of displacement and acceleration responses and ride index comparison. A good performance for the Hybrid Fuzzy-PID controller with coupled rules (HFPIDCR) is achieved in simulation studies despite the nonlinearities.  相似文献   
56.
A benzimidazole derivate, 2‐(1H‐benzimidazol‐2‐yl) phenol (2‐Bip) and its interaction mechanism with sequence specific DNA was examined with Differential Pulse Voltammetry (DPV). We, for the first time, investigated the effect of 2‐Bip on sequence specific DNA with electrochemical methods by evaluating both guanine and 2‐Bip oxidation signal changes. In the study, probe sequences were immobilized to the surface of the electrodes and then hybridization was achieved by sending the complementary target onto the probe modified electrodes. Following the hybridization, 2‐Bip solution was interacted with probe and hybrid sequences to see the effect of 2‐Bip on different DNA sequences. The binding constant (K), toxicity (S%) and thermodynamic parameters, i. e., Gibbs free energy (ΔG°) of 2‐Bip‐DNA complexes were evaluated. K was calculated as 5×105 and the change in the ΔG° was found as ?32.50 kJ mol?1, which are consistent well with the literature. Furthermore, S% showed that 2‐Bip is moderately toxic to single stranded DNA (ssDNA) and toxic to double stranded DNA (dsDNA). From our experimental data, we made four conclusions (i) 2‐Bip affects both ssDNA and dsDNA, (ii) 2‐Bip interaction mode with DNA could be non‐covalent interactions, (iii) 2‐Bip could be used as new DNA hybridization indicator due to its distinct effects on ssDNA and dsDNA, (iv) 2‐Bip could be used as a drug molecule for its DNA effect.  相似文献   
57.
In vitro produced bovine embryos were frozen by pellet freezing or vitrification method. In the pellet freezing method, the embryos were cooled on the dry ice and then frozen as pellets. At warming, the pellets were immersed directly into 0.5 M sucrose. The survival rates of blastocysts frozen by the pellet freezing method were higher (P<0.01) in 40% ethylene glycol (EG) than those in the lower concentrations (20 and 30% EG). Higher survival rates of blastocysts frozen by the pellet freezing method were obtained but the development rates did not differ, as compared with those by the vitrification method. There were no significant differences between the pellet freezing and vitrification method in the frequencies of post-thaw survival of hatched blastocysts. These results demonstrate that the pellet freezing method using dry ice can be used successfully for the cryopreservation of blastocysts.  相似文献   
58.
Herein, a novel pyridine derivative, 1-(2,6 dichlorobenzyl)-4-(2-(2-4-hydroxybenzylidene)hydrazinyl)-pyridinium chloride (DHPC), was synthesized as a candidate drug molecule. Interaction of DHPC with DNA was used to explore its effect on DNA via Differential Pulse Voltammetry, Cyclic Voltammetry, and Electrochemical Impedance Spectroscopy. We demonstrated that oxidation signal of guanine bases of DNA decreased significantly while that of DHPC increased after its interaction with one another. Our candidate drug molecule exhibits LOD and LOQ, e.g., 1.5 μg/mL and 4.9 μg/mL, respectively. Toxicity effect value for DHPC (S%) was calculated as %31, demonstrating the candidate drug molecule's toxic effect on DNA.  相似文献   
59.
Three Re(I) complexes (3, 5, and 7) (Re(CO)3Cl(L)2) and three new Pt(II) complexes (4, 6, and 8) ([Pt(P(Et)3)2(L)2](OTf)2), where L = pyridine, 1 (4-Py-EDOT) or 2 (4-Py-bithiophene), were prepared and characterized. The solid-state structures of 4 and 5 were determined by X-ray crystallography. Electrochromic polymeric films of 2, 5, and 6 were prepared and characterized.  相似文献   
60.
The syntheses and structural elucidations of three different cobalt complexes of m-benziphthalocyanine are reported; both Co(II) and Co(III) complexes can be generated, and the ring undergoes partial oxidation upon metalation with Co(OAc)2x4H2O.  相似文献   
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