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11.
Journal of Thermal Analysis and Calorimetry - Energetic and exergetic performance for an automotive radiator with wavy fin configuration has been investigated and compared for water-based 1% vol.... 相似文献
12.
Ankur Kumar Gupta Vikash Dhindhwal Michael Baer Satyam Ravi Soumya Mukherjee 《Molecular physics》2020,118(12)
By computing the non-adiabatic coupling terms and the adiabatic-to-diabatic transformation angle along closed contours in nuclear configuration space using the CASSCF method and the aug-cc-pVTZ basis set for the lowest three electronic states of HeH2 +, we explore the conical intersection between states in near collinear and noncollinear geometries, particularly in the C 2v geometry. 相似文献
13.
Vikash Dubey 《Journal of Physics and Chemistry of Solids》2004,65(7):1265-1269
Step-annealing schedules for two different annealing chains, i.e. 450-650-450 and 650-450-700 °C have been followed to study the effect of oxygen and carbon on donor formation in carbon-rich Czochralski-silicon. It has been found that the annealing time does not have reasonable effect on substitutional carbon atoms. On the other hand, interstitial oxygen atoms are drastically reduced depending on annealing temperature. Carbon concentration does not exhibit any relationship with new donor (ND) concentration. The result suggests that the ND formation is not controlled by the substitutional carbon concentration directly, but by a density of some unknown embryos. The energy of formation of NDs was found to be 1.84 eV. All these results with plausible explanation are reported here. 相似文献
14.
A constitutive modeling approach for shape memory alloy (SMA) wire by taking into account the microstructural phase inhomogeneity
and the associated solid–solid phase transformation kinetics is reported in this paper. The approach is applicable to general
thermomechanical loading. Characterization of various scales in the non-local rate sensitive kinetics is the main focus of
this paper. Design of SMA materials and actuators not only involve an optimal exploitation of the hysteresis loops during
loading–unloading, but also accounts for fatigue and training cycle identifications. For a successful design of SMA integrated
actuator systems, it is essential to include the microstructural inhomogeneity effects and the loading rate dependence of
the martensitic evolution, since these factors play predominant role in fatigue. In the proposed formulation, the evolution
of new phase is assumed according to Weibull distribution. Fourier transformation and finite difference methods are applied
to arrive at the analytical form of two important scaling parameters. The ratio of these scaling parameters is of the order
of 106 for stress-free temperature-induced transformation and 104 for stress-induced transformation. These scaling parameters are used in order to study the effect of microstructural variation
on the thermo-mechanical force and interface driving force. It is observed that the interface driving force is significant
during the evolution. Increase in the slopes of the transformation start and end regions in the stress–strain hysteresis loop
is observed for mechanical loading with higher rates.
相似文献
15.
Scaling Effects on the Electrochemical Performance of poly(3,4‐ethylenedioxythiophene (PEDOT), Au,and Pt for Electrocorticography Recording
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Mehran Ganji Ahmed T. Elthakeb Atsunori Tanaka Vikash Gilja Eric Halgren Shadi A. Dayeh 《Advanced functional materials》2017,27(42)
Reduced contact size would permit higher resolution cortical recordings, but the effects of diameter on crucial recording and stimulation properties are poorly understood. Here, the first systematic study of scaling effects on the electrochemical properties of metallic Pt and Au and organic poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) electrodes is presented. PEDOT:PSS exhibits better faradaic charge transfer and capacitive charge coupling than metal electrodes, and these characteristics lead to improved electrochemical performance and reduced noise at smaller electrode diameters. PEDOT:PSS coating reduces the impedances of metallic electrodes by up to 18x for diameters <200 µm, but has no effect for millimeter scale contacts due to the dominance of series resistances. Therefore, the performance gains are especially significant at smaller diameters and lower frequencies essential for recording cognitive and pathological activities. Additionally, the overall reduced noise of the PEDOT:PSS electrodes enables a lower noise floor for recording action potentials. These results permit quantitative optimization of contact material and diameter for different electrocorticography applications. 相似文献
16.
Boshier PR Cushnir JR Mistry V Knaggs A Španěl P Smith D Hanna GB 《The Analyst》2011,136(16):3233-3237
A study is described of the first on line, real time analyses of the exhaled breath of five anaesthetized patients during the complete perioperative periods of laparoscopic surgery. These breath analyses were achieved using a selected ion flow tube, SIFT-MS, instrument, located in the operating theatre at an acceptable distance from the operating table, and coupled to the endotracheal tube in the ventilation circuit via a 5 metre long capillary tube. Thus, inhalation/exhalation breathing cycles, set to be at a frequency of 10 per minute, were sampled continuously for water vapour, the metabolites acetone and isoprene and the propofol used to induce anaesthesia for each operating period that ranged from 20 min (shortest) to 80 min (longest). Whilst there was some loss of water vapour along the long sampling line, the concentrations of the other trace compounds were not diminished. The breath acetone was essentially at a constant level for each patient, but increased somewhat over the longest operating period due to the onset of lipolysis. Most interesting is the clear increase of breath isoprene following abdomen inflation with carbon dioxide. The vapour of the intravenously injected propofol was detected in the exhaled breath and remained essentially constant during the perioperative period. These analyses were performed totally non-invasively and the data were immediately and constantly available to the anaesthetist and surgeon. Exploitation of this development could influence decision making and potentially improve patient safety within the perioperative setting. 相似文献
17.
Dr. Antara Pal Dr. Vikash Malik Dr. Le He Dr. Ben H. Erné Prof. Dr. Yadong Yin Prof. Dr. Willem K. Kegel Dr. Andrei V. Petukhov 《Angewandte Chemie (International ed. in English)》2015,54(6):1803-1807
Manipulation of the self‐assembly of magnetic colloidal particles by an externally applied magnetic field paves a way toward developing novel stimuli responsive photonic structures. Using microradian X‐ray scattering technique we have investigated the different crystal structures exhibited by self‐assembly of core–shell magnetite/silica nanoparticles. An external magnetic field was employed to tune the colloidal crystallization. We find that the equilibrium structure in absence of the field is random hexagonal close‐packed (RHCP) one. External field drives the self‐assembly toward a body‐centered tetragonal (BCT) structure. Our findings are in good agreement with simulation results on the assembly of these particles. 相似文献
18.
Abhishek Swarnkar Ramya Chulliyil Vikash Kumar Ravi Dr. Mir Irfanullah Dr. Arindam Chowdhury Dr. Angshuman Nag 《Angewandte Chemie (International ed. in English)》2015,54(51):15424-15428
Traditional CdSe‐based colloidal quantum dots (cQDs) have interesting photoluminescence (PL) properties. Herein we highlight the advantages in both ensemble and single‐nanocrystal PL of colloidal CsPbBr3 nanocrystals (NCs) over the traditional cQDs. An ensemble of colloidal CsPbBr3 NCs (11 nm) exhibits ca. 90 % PL quantum yield with narrow (FWHM=86 meV) spectral width. Interestingly, the spectral width of a single‐NC and an ensemble are almost identical, ruling out the problem of size‐distribution in PL broadening. Eliminating this problem leads to a negligible influence of self‐absorption and Förster resonance energy transfer, along with batch‐to‐batch reproducibility of NCs exhibiting PL peaks within ±1 nm. Also, PL peak positions do not alter with measurement temperature in the range of 25 to 100 °C. Importantly, CsPbBr3 NCs exhibit suppressed PL blinking with ca. 90 % of the individual NCs remain mostly emissive (on‐time >85 %), without much influence of excitation power. 相似文献
19.
Yadav VK Kumar V Chhikara N Kumar S Manral P Kashav T Saini S Srinivasan A Singh S Singh TP Yadav S 《Journal of separation science》2011,34(9):1076-1083
The seminal plasma comprises secretions from various accessory sex glands. During fertilization spermatozoa undergo complex sequences of precisely timed events that are regulated by the activation of different intracellular signaling pathways. The precision and efficacy of these pathways are often influenced by the assembly and interactions of multiprotein complexes, thereby directing the flow of regulatory information. Our knowledge about these protein complexes present in human seminal plasma (HuSP) is limited. Here we report the identification and characterization of a native high molecular weight zinc-binding multiprotein complex from HuSP by utilizing 2-DE followed by MS. Twenty-six proteins representing isoforms and/or fragments of 11 different proteins were found to be assembled in this complex. Prostate-specific antigen, zinc α2-glycoprotein, prostatic acid phosphatase, and prolactin inducible protein were the major proteins of this complex. Dynamic light scattering experiments revealed changes in aggregation pattern accompanied with deviation from physiological pH and in presence of SDS. However, no significant changes were observed in the presence of physiological ligands such as zinc and fructose. The present study will be useful and contribute to guide the future studies performed for elucidation of biological significance of this native complex in HuSP. 相似文献
20.