Article history: Received on: 09/03/2013 Accepted on: 07/05/2013 Available online: 30/05/2013 Paris fargesii is a famous Chinese traditional medicinal plant used as antipyretic, antidotal, antiphlogistic and analgesic. This research aimed at the determination of the total polysaccharides contents in P. fargesii, which were collected from Baoxing country of Sichuan Province in order to get the o...

Inviscid traveling waves are ghost-like phenomena that do not appear in reality because of their instability. However, they are the reason for the complexity of the traveling wave theory of reaction-diffusion equations and understanding them will help to resolve related puzzles. In this article, we obtain the existence, the uniqueness and the regularity of inviscid traveling waves under a gener...

The principle of the traveling wave based differential protection for bipolar HVDC transmission lines is proposed in the paper. Unlike the traditional current differential protection, the quantity of current is replaced by the quantity of the traveling wave for comparison. The traveling wave at the remote end is transferred to the local end for comparison to the local traveling wave. For the bi...

In general the ultrasonic testing is used for flaw detection and localization in tested materials. Flaws in materials are commonly characterized in measured ultrasonic signals by faults echoes. Ultrasonic signals measured on materials with coarse grained structure contain relative high level of noise. This undesirable part of ultrasonic signal should be reduced to make the fault echo detection ...

background: ultrasonography is an imaging method which, due to its relative economy, is becoming more widely available in regions of the world where fasciola hepatica infection occurs most frequently. in this report, we describe the sonographic findings of hepatic lesions in patients with fascioliasis to help confirmation of the sonographic characteristics of this disease and thus aid in its di...

Traveling surges are commonly adopted in protection devices of high-voltage direct current (HVDC) transmission systems. Lightning strikes also can produce large-amplitude traveling surges which lead to the malfunction of relays. To ensure the reliable operation of protection devices, recognition of traveling surges must be considered. Wavelet entropy, which can reveal time-frequency distributio...

This document presents the principle of ultrasonic distance measurement is described, the main error sources of ultrasonic distance measurement are analyzed also. A method of improving precision of ultrasonic distance measurement in air, in which the transmission speed of ultrasonic wave if corrected by measured air temperature and the forward edge of receive wave can be determined accurately b...

Aiming at the problem that echo signal is hard to recognize caused by ultrasonic energy’s overquick dispersion and attenuation, a kind of ultrasonic horn is designed. According to the acoustic theory analysis, the ultrasonic horn can increase its radiation energy by improving impedance matching. The ultrasonic horn can make the directivity of sound source sharper and energy more centralized bec...

it has been proved that ultrasonic energy can considerably increase the amount of oil recovery in animmiscible displacement process. although many studies have been performed on investigating theroles of ultrasonic waves, based on the best of our knowledge, little attention has been paid to evaluatewave attenuation parameter, which is an important parameter in the determination of the energydel...

continuous exposure to high-energy ultrasonic waves depolymerises macromolecules in solutions and produces a permanent reduction in viscosity. different factors affect the efficiency of this ultrasonic depolymerisation. in this work ultrasonic degradation of one commercially important hydrogel based on acrylic acid and acrylamide was carried out in aqueous solution at room temperature (25oc). a...