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1.
Frank Rutz Martin Koch Shilpa Khare Martin Moneke Heike Richter Uwe Ewert 《International Journal of Infrared and Millimeter Waves》2006,27(4):547-556
We report on experiments that evaluate the potential of terahertz (THz) time-domain spectroscopy (TDS) for quality control
of polymeric compounds. We investigate specimens out of a polyethylene compound with silver-coated titanium dioxide nanospheres
and a glass-fiber reinforced epoxy composite. We further examine an industrial polymer product produced by injection molding.
Our data demonstrates that THz imaging is a powerful tool for contactless quality control in the polymer industry. 相似文献
2.
Transverse flow transversely excited (TFTE) CO2 lasers are easily scalable to multikilowatt level. The laser power can be scaled up by increasing the volumetric gas flow
and discharge volume. It was observed in a TFTE CW CO2 laser having single row of pins as an anode and tubular cathode that the laser power was not increasing when the discharge
volume and the gas volumetric flow were increased by increasing the electrode separation keeping the gas flow velocity constant.
The discharge voltage too remained almost constant with the change of electrode separation at the same gas flow velocity.
This necessitated revision of the scaling laws for designing this type of high power CO2 laser. Experimental results of laser performance for different electrode separations are discussed and the modifications
in the scaling laws are presented. 相似文献
3.
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5.
Sandip Kumar Dash Minakshi Sharma Shashi Khare Ashok Kumar 《Applied biochemistry and biotechnology》2013,171(1):198-208
Human brain bacterial meningitis is a life-threatening disease caused mainly by Neisseria meningitidis, lead to damage of the outer membrane covering (meninges) of brain or even death. The usual methods of diagnosis are either time-consuming or have some limitations. The specific rmpM (reduction-modifiable protein M) virulent gene based genosensor is more sensitive, specific, and can detect N. meningitidis directly from the patient cerebrospinal fluid in 30 min including 1-min response time. 5′-Thiol-labeled single-stranded DNA (ssDNA) probe was immobilized onto screen-printed gold electrode (SPGE) and hybridized with denatured (95 °C) single-stranded genomic DNA (ssG-DNA) for 10 min at 25 °C. The electrochemical response was measured by cyclic voltammetry, differential pulse voltammetry (DPV) and electrochemical impedance using redox indicators. The sensitivity of the genosensor was 9.5087?(μA/cm2)/ng with DPV and limit of detection was 3 ng/6 μL ssG-DNA. The immobilization of the ssDNA probe and hybridization with ssG-DNA from N. meningitidis was characterized by atomic force microscopy and Fourier transform infrared spectroscopy. The rmpM genosensor was stable for 6 months at 4 °C with 10 % loss in initial DPV current. The advantage of rmpM genosensor is to detect bacterial meningitis simultaneously in multiple patients using SPGE array during an outbreak of the disease. 相似文献
6.
In this paper an alternative approach for measurement of στ product for 4
F
3/2→4
I
11/2 transition of Nd3+ doped YVO4 crystal is reported. In this method a microchip laser is formed by keeping a small piece of the sample in plane-plane resonator
and a diode laser (808 nm) is used for pumping. The pump power induced thermal lensing effect is used to make the cavity stable.
The cavity mode area is estimated by measuring the thermal lens focal length at the threshold and the average pump area is
measured by Gaussian fit to the intensity profiles of the pump beam. The value of στ product of Nd:YVO4 crystal obtained by this method is within 10% of the reported values. The advantage of this method is that it is a simple
method for direct measurement of στ product of laser crystals. 相似文献
7.
We consider linear representations of the Galois groups of number fields in two different characteristics and examine conditions under which they arise simultaneously from a motive. 相似文献
8.
Flavonoids are chemical moieties widely distributed in certain plants that are important biologically active constituents of a daily human diet, with significant pharmacological potential (anti-hepatotoxic, anti-allergic, anti-inflammatory, anti-osteoporotic, and anti-tumor activities). Thus keeping in view the importance of this class of compounds, a rapid method for the separation and identification of fifteen phenols belonging to six different types of phenolics in a sole analysis has been developed and validated using selectivity, precision, recovery, and robustness as parameters. The method developed, which is rapid, accurate, and robust for the analysis of different classes of phenols, can be used in the quality control and standardization of plant extracts as well as herbal drugs, including compound herbal formulations. 相似文献
9.
10.
R. Khare P.K. Shukla G.K. Mishra C. Mukherjee S. Talwar V.K. Dubey P. Saxena J.K. Mittal 《Optics Communications》2009,282(19):3850-3853
We present an analytical and experimental study of a novel confocal optical pulse stretcher (COPS). The simple and passive pulse stretcher consists of two concave mirrors and a scraper beam-splitter and its optical configuration ensures a perfect spatial overlapping of laser pulses at the beam-splitter. The pulse stretcher is compact and suitable for laser pulses of large divergences. The confocal optical pulse stretcher is demonstrated on a pulsed copper vapour laser to convert a 40 ns (1/e2 % points) pulse into a 55 ns with reduction of peak power by a factor of 1.375 without loss of pulse energy. 相似文献