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1.
B V Bahuguna Saradhi G Prasad G S Kumar T Bhimasankaram 《Bulletin of Materials Science》1999,22(4):779-783
Impedance of sintered discs of 0·1, 0·25, 0·4 mol% of sodium metavanadate was measured in the frequency range 10 kHz-1 MHz
and in the temperature region from room temperature (=30°C) to 450°C. AC conductivity was calculated from the data. DC conductivity
was measured in the temperature range 150–450°C. Debye type of relaxation effects were observed in the dielectric loss. The
activation energy of the dipoles involved in relaxation was estimated. The activation energy for AC conduction in the temperature
above 380°C was calculated. These values are larger than the activation energy of pure sodium metavanadate sample. The relaxation
phenomenon observed is explained. 相似文献
2.
The effect of hall currents on the magneto hydro dynamic (MHD) boundary layer flow over a flat plate
V. G. Naidu Prof. S. R. Koneru Dr. H. R. Nataraja Dr. B. N. Rao 《Forschung im Ingenieurwesen》1990,56(4):129-132
Studies are made on laminar compressible magneto hydro dynamic (MHD) boundary layer flow over a flat-plate with Hall and ionslip
currents. Viscous drag, magnetic drag and heat transfer coefficients are determined for the values of interaction parameter,
electromagnetic load parameter, Hall parameter and ionslip current parameter. It is found that the overall drag (magnetic
plus viscous) coefficient increases and the heat transfer coefficient decreases with interaction parameter. 相似文献
3.
V Sundaram AN Hanna L Koneru HA Newman JM Falko 《Canadian Metallurgical Quarterly》1997,82(10):3421-3424
Hypothyroidism is frequently associated with hypercholesterolemia and an increased risk for atherosclerosis, whereas hyperthyroidism is known to precipitate angina or myocardial infarction in patients with underlying coronary heart disease. We have shown previously that L-T4 functions as an antioxidant in vitro and inhibits low density lipoprotein (LDL) oxidation in a dose-dependent fashion. The present study was designed to evaluate the changes in LDL oxidation in subjects with hypothyroidism and hyperthyroidism. Fasting blood samples for LDL oxidation analyses, lipoprotein determinations, and thyroid function tests were collected at baseline and after the patients were rendered euthyroid. The lag phase (mean +/- SEM hours) of the Cu+2-catalyzed LDL oxidation in the hypothyroid state and the subsequent euthyroid states were 4 +/- 0.0.65 and 14 +/- 0.68 h, respectively (P < 0.05). The lag phase during the hyperthyroid phase was 6 +/- 0.55 h, and that during the euthyroid phase was 12 +/- 0.66 h (P < 0.05). The total and LDL cholesterol levels were higher in hypothyroidism than in euthyroidism and were lower in hyperthyroidism than in the euthyroid state. We conclude that LDL has more susceptibility to oxidation in both the hypothyroid and hyperthyroid states. Thus, the enhanced LDL oxidation may play a role in the cardiac disease process in both hypothyroidism and hyperthyroidism. 相似文献
4.
Xu Shao Luying Zhou Xiaofei Cheng Chava Vijaya Saradhi Yixin Wang Jianqing Li 《Photonic Network Communications》2008,16(3):221-231
For 100% shared risk link group (SRLG) failure protection, conventional full path protection has to satisfy SRLG-disjoint
constraints, i.e., its working path and backup path cannot go though the same SRLG. With the increase of size and number of
SRLGs, capacity efficiency of conventional shared full path protection becomes poorer due to SRLG-disjoint constraints and
the blocking probability becomes much higher due to severe traps. To solve these problems, we present a partial path protection
scheme where SRLG-disjoint backup paths may only cover part of the working path. Full path protection becomes a special case
of partial path protection, in which the backup path covers the full working path. By choosing the most survivable partial
backup path as backup path, we can make the impact of SRLG failures as low as possible and accept as many as possible connection
requests. Assuming every SRLG has the same probability to fail, we present a heuristic algorithm to find the most survivable
partial backup path by choosing full path protection first, iteratively computing partial backup paths and choosing the most
survivable one. The benefit of this heuristic algorithm is that it can find the optimal results within less iteration. Analytical
and simulation results show that, compared to conventional full path protection, our proposed scheme can significantly reduce
blocking probability with little sacrifice on survivability. The proposed scheme is very useful particularly when the network
contains a lot of SRLGs and the blocking probability of conventional full path protection becomes too high.
相似文献
Jianqing LiEmail: |
5.
Pragney Deme Tirupathi Azmeera Sanjit Kanjilal Padmaja Jonnalagadda Vijaya Saradhi Upadhyayula 《Food Analytical Methods》2013,6(4):1162-1169
A simple and specific analytical method based on solid phase extraction (SPE), and liquid chromatography–electrospray ionization–tandem mass spectrometry (LC-ESI-MS/MS) operated in multipule reaction monitoring (MRM) mode with dynamic time segment acquisition windows, was developed to determine organophosphorus pesticide residues (acephate, monocrotophos, dimethoate, malaoxon, dichlorvos, malathion, phenthoate, parathion-ethyl, chlorfenvinfos, quinalphos, diazinon, phosalone, profenofos, ethion, chlorpyrifos) in tender coconut water. The method was observed to be linear with lower limit of detections ranged from 0.1 to 1.5 ng/mL (measured at S/N ratio 5:1) and limit of qunatitation 0.5 to 2.0 ng/mL (measured at S/N ratio 10:1) for all studied pesticides. The intra- and inter-day assay accuracies calculated at four concentration levels in six replicates (n?=?6) were in the range of 80 % to 115 % with relative standard deviations (RSD) below 15 %. The percentage recoveries of all the analysed pesticides were in the range of 86.8 % to 107.6 % and the calculated RSD values were below 12 %. The developed method was applied to determine pesticide residues in natural tender coconut water samples. The results showed the presence of malathion ranging from 24 to 45 ng/L concentrations in some natural tender coconut water samples collected from various local market places in and around Hyderabad, Andhra Pradesh, India. 相似文献
6.
Kalidindi Kishore Raju Gottumukkala Pardha Saradhi Varma Davuluri Rajyalakshmi 《The Journal of supercomputing》2020,76(8):5873-5898
The Journal of Supercomputing - Images (HSIs) are popular in diversified applications, such as geosciences, biomedical imaging, molecular biology, agriculture, astronomy, food quality and safety... 相似文献
7.
The term oculocutaneous albinism (OCA) covers a range of autosomal recessive genetic conditions involving hypopigmentation of the skin, hair, and eyes. In southern African black ethnic groups the tyrosinase positive form, OCA2, is predominant, with few cases of tyrosinase negative OCA1. The prevalence of OCA2 in schoolchildren in Harare, the capital city of Zimbabwe, was found to be 1 in 2833. The gene frequency for OCA2 was 0.0188, with a carrier frequency of 1 in 27. Most of the pupils with albinism belong to the majority Shona ethnic group. As consanguineous marriages are discouraged in the Shona culture this high rate is likely to be a result of genetic drift in a relatively small population showing limited mobility. OCA pupils were found in more than a third of the secondary schools in Harare, emphasising the importance of distributing information on albinism and its management widely throughout the school system. 相似文献
8.
Wavelength division multiplexed (WDM) networks are matured to provide, scalable data centric infrastructure, capable of delivering flexible, value added, high speed and high bandwidth services directly from the optical domain. Optical virtual private networks (OVPNs) make use of the concept of highly reconfigurable nature of lightpaths offered by WDM, to create secure tunnels of high bandwidth across the intelligent WDM optical transport network. An OVPN is a private connection between two or more edge devices (access nodes), that allows a group of clients to fully exploit the flexibility of the switched intelligent optical network. However, OVPNs will not be a viable alternative unless they can guarantee a predictable bandwidth, availability, response time, and fault-tolerance to users. In this paper, we study the problem of dynamically establishing lightpaths for OVPNs over intelligent optical transport networks to provide varying classes of service based on the type of primary and backup lightpaths and the number of backup lightpaths, when each OVPN is specified by the desired logical connectivity and Class of Service. The type of primary and backup lightpaths determines the QoS parameters such as response time and bandwidth. Whereas, the number of backup lightpaths determines the level of fault-tolerance and availability of OVPN. Based on the service classes, any OVPN in the network falls into one of the six classes viz. single dedicated primary and single dedicated backup (SDPSDB), single dedicated primary and multiple dedicated backups (SDPMDB), single dedicated primary and single shared backup (SDPSSB), single shared primary and single shared backup (SSPSSB), single shared primary and multiple shared backups (SSPMSB), and best-effort (BE). In BE, we consider two variations—(1) OVPN as dedicated logical ring topology (DLRT) and (2) OVPN as shared logical ring topology (SLRT). We conduct extensive simulation experiments to compare and evaluate the effectiveness of different classes of OVPNs for varying network configurations–varying number of fibers, wavelengths on physical links, and number of nodes in OVPN. 相似文献
9.
Differentiated QoS for survivable WDM optical networks 总被引:1,自引:0,他引:1
Optical networks based on WDM technology have become a promising solution to realize transport networks that can meet the ever-increasing demand for bandwidth. As WDM networks carry a huge volume of traffic, maintaining a high level of survivability is an important and critical issue. The. development of GMPLS switching technology led to the direct integration of IP and WDM. In these IP-over-WDM networks different applications/end users need different levels of fault tolerance and differ in how much they are willing to pay for the service they get. The current trend in network development is moving toward a unified solution providing support for voice, data, and various multimedia services. Therefore, it imperative that WDM networks incorporate fault tolerance to single or multiple component failures, protection bandwidth, recovery time, and recovery granularity besides resource utilization and call acceptance ratio. This article presents a survey of various methods that have been proposed for providing service differentiation in survivable WDM networks and discuss their performance. Such methods are broadly classified under various paradigms such as differentiated reliability, R-connections, quality of protection, and quality of recovery. 相似文献
10.
Obese Zucker rats are susceptible to increased hepatic ischemia/reperfusion (I/RP) injury. Increased lipid peroxidation occurs in this model with warm ischemia. We hypothesized that a severe depletion of phospholipids (PL) occurs with warm I/RP in fatty livers. Obese (Ob) and lean (Ln) Zucker rats were subjected to 90 min of in vivo partial hepatic warm I followed by RP. Total lipids extracted from one gm of liver (median lobe) taken at the end of 1, 2 and 6 hr of RP and sham (Sh) surgery (n=5 Ln & Ob) were analyzed by 202.3 MHz 31P NMR, which provided good resolution of individual PL. Obese (Sh) rats contained 22% more PL than Ln (P= < 0.01). Ischemia caused similar decreases in PL in both Ob (to 67% Sh) and Ln rats (62%). Following 2 hr RP, PL in Ob rats decreased further (46% Sh) and recovered only marginally at 6 hr (53%), in marked contrast to the rapid recovery in Ln to preischemic levels (110% Sh at both 2 and 6 hr; P=<0.001). Mole percents of individual PL did not change significantly except for lysophosphatidylcholine, which increased from 0.43 to 1.3% (Sh vs. 6 hr RP) in the Ob, but decreased from 0.98 to 0.52% in Ln animals (P = <0.001). Fatty livers thus are more vulnerable to phospholipid depletion in response to warm ischemia/reperfusion than normal livers. 相似文献