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41.
Vivekanand V Dwivedi P Pareek N Singh RP 《Applied biochemistry and biotechnology》2011,165(1):204-220
In solid-state fermentation, among various solid supports evaluated, banana peel was found to be an ideal support and resulted
into higher levels of laccase (6281.4 ± 63.60 U l−1) along with notable levels of manganese peroxidase production (1339.0 ± 131.23 U l−1) by Aspergillus fumigatus VkJ2.4.5. Maximum levels of laccase was achieved under derived conditions consisting of 80% of moisture level, 6 days of
incubation period, 6% inoculum level, and an aeration level of 2.5 l min−1. A column-tray bioreactor was designed to scale up and economize the enzyme production in three successive cycles of fermentation
using the same fungal biomass. Thermal and pH stability profiles revealed that enzyme was stable up to 50°C and at varying
pH range from 5–9 for up to 2 h. The apparent molecular weight of laccase was found to be 34 ± 1 kDa. MALDI-TOF/TOF analysis
of the protein showed significant homology with maximum identity of 67% to other laccases reported in database. 相似文献
42.
M. Bonanzinga M. V. Matveev C. M. Pareek 《Rendiconti del Circolo Matematico di Palermo》2002,51(1):163-174
We prove some propositions and present some examples concerning the properties between countably compact and pseudocompact and the properties between Lindelöf and pseudo-Lindelöf. 相似文献
43.
Milton SV Gluskin E Biedron SG Dejus RJ Den Hartog PK Galayda JN Kim K Lewellen JW Moog ER Sajaev V Sereno NS Travish G Vinokurov NA Arnold ND Benson C Berg W Biggs JA Borland M Carwardine JA Chae Y Decker G Deriy BN Erdmann MJ Friedsam H Gold C Grelick AE 《Physical review letters》2000,85(5):988-991
Experimental evidence for self-amplified spontaneous emission (SASE) at 530 nm is reported. The measurements were made at the low-energy undulator test line facility at the Advanced Photon Source, Argonne National Laboratory. The experimental setup and details of the experimental results are presented, as well as preliminary analysis. This experiment extends to shorter wavelengths the operational knowledge of a linac-based SASE free-electron laser and explicitly shows the predicted exponential growth in intensity of the optical pulse as a function of length along the undulator. 相似文献
44.
45.
46.
V K Senecha Y B S R Prasad M P Kamath A S Joshi G S Solanki A P Kulkarni S Gupta R Pareek H C Pant 《Pramana》2000,55(5-6):789-795
An investigation of x-ray emission from Cu plasma produced by 1.054 μm Nd:glass laser pulses of 5 ns duration, at 2 × 1012 − 2 × 1013 W cm−2 is reported. The x-ray emission has been studied as a function of target position with respect to the laser beam focus position.
It has been observed that x-ray emissions from ns duration plasma show a volume effect similar to subnanosecond plasmas. Due
to this effect the x-ray yield increases when target is moved away relative to the best focal plane of the laser beam. This
result supports the theoretical model of Tallents and has also been testified independently using suitably modified theoretical
model for our experimental conditions. While above result is in good agreement with similar experimental results obtained
for sub-nanosecond laser produced plasmas, it differs from result claiming filamentation rather than pure geometrical effect
leading to x-ray enhancement for ns plasmas. 相似文献
47.
Infrared-to-visible wave-length conversion in the Yb3+−Er3+ doped phosphors system has been described by a simple three level model based on two ions mechanism. The excitation in the
range of 900–1000 nm of an IR-photon is first absorbed by Yb3+ ion as a sensitizer attributed to the resonant energy transition in Er3+ ion from 4
I
3/2 → 4
S
15/2 and 1
F
9/2 → 4
I
15/2, respectively for green and red emission. The essential energy transfer processes in this system i.e. upconversion from 4
I
11/2 and 1
I
13/2, cross-relaxation from 4
S
3/2 and 1
F
9/2 are taken into account. The limitations of the rate-equation approach are examined with a focus on the underlying dynamics
of this rare-earth system. 相似文献
48.
In this paper, detailed theoretical investigation on the frequency response and responsivity of a strain balanced SiGeSn/GeSn quantum well infrared photodetector (QWIP) is made. Rate equation and continuity equation in the well are solved simultaneously to obtain photo generated current. Quantum mechanical carrier transport like carrier capture in QW, escape of carrier from the well due to thermionic emission and tunneling are considered in this calculation. Impact of Sn composition in the GeSn well on the frequency response, bandwidth and responsivity are studied. Results show that Sn concentration in the GeSn active layer and applied bias have important role on the performance of the device. Significant bandwidth is obtained at low reverse bias voltage, e.g., 200?GHz is obtained at 0.28?V bias for a single Ge0.83Sn0.17 layer. Whereas, the maximum responsivity is of 8.6?mA/W at 0.5?V bias for the same structure. However, this can be enhanced by using MQW structure. 相似文献
49.
50.
Pawan Kumar Pareek Mithlesh Prashant Kriplani Ravikant Kishan Gopal Ojha 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1338-1345
2,4,6-Substituted 1,3,5-tris(benzothiazolyl)hexahydro-1,3,5-triazine derivatives were synthesized by the condensation of substituted benzothiazoles with aldehydes by conventional as well as by microwave irradiation (solvent free and solid supported) methods. All compounds were tested for antibacterial and antifungal activities, and the results have been compared with standard drugs. Acaricidal and anti-feedant activities were also tested. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献