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排序方式: 共有417条查询结果,搜索用时 10 毫秒
381.
In this study, Pergularia milkweed fibre (70%), cotton fibre (30%) core and 100% cotton fibre sheath DREF-3 core yarns of 74?tex were produced using different spinning parameters in order to understand their effect on yarn properties. Box–Behnken design was used for the optimization of core ratio, drum speed and suction pressure, and to evaluate the effects and interactions of the process variables on the yarn properties at a constant opening roller speed of 12,000?rpm and production speed of 100?m/min. The effects of the core/sheath ratio on all the yarn properties are significant. With an increase in the core/sheath ratio, yarn tenacity and elongation decrease due to insufficient wrapper fibres in the yarn and yarn unevenness; imperfection increases due to higher feed rate and draft at higher core ratio. The yarn hairiness increases at higher core ratio due to higher number of short fibres in milkweed and lesser sheath fibres to cover the core fibres effectively. An increase in the spinning drum speed damages fibre in the sheath and increases the number of hooks at the end of fibres, as a result of which the core yarn tenacity decreases at higher drum speed. At a higher air suction pressure, yarn tenacity and the elongation at break increases. The drum speed and suction pressure have no significant effect on yarn unevenness and imperfections. The yarn hairiness decreases slightly with increase in drum speed and suction pressure but is insignificant. 相似文献
382.
Rajan Murugan Karuppusamy Arunachalam Thangaraj Parimelazhagan 《Food science and biotechnology》2012,21(1):59-67
In the present investigation, phenolics (36.6 g gallic acid equivalents (GAE)/100 g extract), tannin (21.6 g GAE/100 g extract),
and flavonoid content (67.5 g rutin equivalents/100 g extract) were found to be highest in acetone extract. Ficus (Ficus amplissima) acetone extract showed maximum antioxidant activity in phosphomolybdenum (958.8 mg ascorbic acid equivalents/g extract),
DPPH (1.6 μg/mL), ferric reducing antioxidant power (2,993 mmol Fe (II)/g extract), and metal chelating (39.7 mg EDTA equivalents/g
extract) assays. In anti-inflammatory study, 400 mg/kg acetone extract showed maximum reduction in the paw volume compare
to indomethacin. GC-MS analysis indicated that bark contain rich source of non-polar compounds like Lup-20(29)-en-3-yl acetate
(33.04%). Hence, Ficus can be valuable source for antioxidant and anti-inflammatory and seemed to be applicable in medicine. 相似文献
383.
This paper investigates the accelerated mixing of hot and cold liquid layers in storage tanks of different physical dimensions by the application of high-frequency, high-intensity pulsed ultrasound. In pulsed operation, the ultrasonic field is switched on for a few seconds and then switched off. This cycle is repeated several times. Pulsed mixing of hot and cold water due to ultrasonics was measured in this study. Acoustic streaming and cavitation phenomena associated with the ultrasonic field can induce enhanced mixing in the storage containers leading to de-stratification of liquid. The experimental results indicate that dual frequency operation, which combines one high-frequency mode with one low-frequency mode, is optimal in enhancing mixing compared to other frequencies. Mixing efficiency increases with cavitation intensity and the introduction of acoustic streaming augments it further. The experimental result indicates that as the height of the cylinder increases, the mixing time also increases. The ultrasonic mixing times obtained for different frequencies indicate that as the frequency increases, the time required to reach the steady state temperature also increases, due to decrease in cavitation intensity. 相似文献
384.
Biogenic silica synthesised from rice husk was used as a controlled release system of an eco‐friendly biocide consisting of a Justicia adhatoda extract. Fourier‐transform infrared spectroscopy (FTIR) indicated the presence of ester bonds between the silica support and the conjugated Justicia adhatoda extract. Surface area analysis and microscopy confirmed a high level of Justicia adhatoda extract loading in the silica support. The phytochemical investigation of Justicia adhatoda was done by Gas chromatography–mass spectrometry (GC‐MS) spectroscopy. Moreover, compared with the naked biogenic silica nanoparticles, a better thermal stability was determined for the conjugated system of the extracted compounds. Trial of kinetic release of silica: Justicia adhatoda ∼29% of loaded Justicia adhatoda was released within 1 h and then the rate of release became slow. Net release of Justicia adhatoda was observed up to 50% within 7 h. The Justicia adhatoda compounds released from silica also showed the improved mortality rate against stored product pest rice weevil (Sitophilus oryzae). 相似文献
385.
Mahesh Ramalingam Han-Seong Jeong Jinsu Hwang Hyong-Ho Cho Byeong C. Kim Eungpil Kim Sujeong Jang 《International journal of molecular sciences》2022,23(8)
Rotenone (ROT) inhibits mitochondrial complex I, leading to reactive oxygen species formation, which causes neurodegeneration and alpha-synuclein (α-syn) aggregation and, consequently, Parkinson’s disease. We previously found that a neurogenic differentiated human adipose tissue-derived stem cell-conditioned medium (NI-hADSC-CM) was protective against ROT-induced toxicity in SH-SY5Y cells. In the present study, ROT significantly decreased the phospho (p)-mTORC1/total (t)-mTOR, p-mTORC2/t-mTOR, and p-/t-ULK1 ratios and the ATG13 level by increasing the DEPTOR level and p-/t-AMPK ratio. Moreover, ROT increased the p-/t-Akt ratio and glycogen synthase kinase-3β (GSK3β) activity by decreasing the p-/t-ERK1/2 ratios and beclin-1 level. ROT also promoted the lipidation of LC3B-I to LC3B-II by inducing autophagosome formation in Triton X-100-soluble and -insoluble cell lysate fractions. Additionally, the levels of ATG3, 5, 7, and 12 were decreased, along with those of lysosomal LAMP1, LAMP2, and TFEB, leading to lysosomal dysfunction. However, NI-hADSC-CM treatment increased the p-mTORC1, p-mTORC2, p-ULK1, p-Akt, p-ERK1/2, ATG13, and beclin-1 levels and decreased the p-AMPK level and GSK3β activity in response to ROT-induced toxicity. Additionally, NI-hADSC-CM restored the LC3B-I level, increased the p62 level, and normalized the ATG and lysosomal protein amounts to control levels. Autophagy array revealed that the secreted proteins in NI-hADSC-CM could be crucial in the neuroprotection. Taken together, our results showed that the neuroprotective effects of NI-hADSC-CM on the autophagy signaling pathways could alleviate the aggregation of α-syn in Parkinson’s disease and other neurodegenerative disorders. 相似文献
386.
Acute bioassay tests were conducted with the organochlorine pesticide, lindane on Colisa lalia. LC50 and its 95% upper and lower confidence limits for different periods of exposure were determined. A toxicity curve was constructed from which is derived the lethal threshold concentration for Colisa to lindane. The fish were exposed to two selected concentrations viz., 0.1 and 0.37 mg 1?1 for 96 and 6 h respectively and their behaviour and bimodal respiration were studied. Erratic behavioural responses were noticed at 0.37 mg 1?1 whereas the response at 0.1 mg 1?1 were orderly and adaptive. Total oxygen consumption of fish increased but the dependence on the type of respiration differed in the two concentrations, and this selective dependence at 0.1 mg 1?1 is suggested to have survival value. 相似文献
387.
BN Murthy R Ezhil S Venkatasubramanian N Ramalingam V Periannan R Ganesan N Ramani V Selvaraj 《Canadian Metallurgical Quarterly》1995,32(1):129-135
The reaction mechanisms of p-nitrophenyl phosphate hydrolysis catalyzed by two rat liver isoenzymes of the low M(r) phosphotyrosine protein phosphatase (AcP1 and AcP2) were compared. Furthermore, the effect of some heterocyclic compounds on their activities were tested. Cyclic GMP and guanosine causes a particularly high activation of the isoenzyme AcP2, whereas its effect on AcP1 is very poor. A study on the mechanism of cyclic GMP activation was carried out. The results suggest that cyclic GMP activates the AcP2 isoenzyme by increasing the rate of the step that leads to the hydrolysis of the covalent enzyme-substrate phosphorylated complex formed during the catalytic process. The physiological significance of cyclic GMP activation of only one of the two isoenzymes (AcP2) remains uncertain. 相似文献
388.
There is a strong and urgent need for efficient materials that can capture radioactive iodine atoms from nuclear waste. This work presents a novel strategy to develop porous materials for iodine capture by employing halogen bonding, mechanochemistry and crystal engineering. 3D halogen-bonded organic frameworks (XOFs) with guest-accessible permanent pores are exciting targets in crystal engineering for developing functional materials, and this work reports the first example of such a structure. The new-found XOF, namely TIEPE-DABCO , exhibits enhanced emission in the solid state and turn-off emission sensing of acid vapors and explosives like picric acid in nanomolar quantity. TIEPE-DABCO captures iodine from the gas phase (3.23 g g−1 at 75 °C and 1.40 g g−1 at rt), organic solvents (2.1 g g−1), and aqueous solutions (1.8 g g−1 in the pH range of 3–8); the latter with fast kinetics. The captured iodine can be retained for more than 7 days without any leaching, but readily released using methanol, when required. TIEPE-DABCO can be recycled for iodine capture several times without any loss of storage capacity. The results presented in this work demonstrate the potential of mechanochemical cocrystal engineering with halogen bonding as an approach to develop porous materials for iodine capture and sensing. 相似文献
389.
K Ramalingam 《Canadian Metallurgical Quarterly》1976,41(1):131-138
Water deprivation for 48 hr with its accompanying decrease in food intake significantly lowered the in vitro rate of hexobarbital metabolism by hepatic microsomes isolated from male rats. Pair-fed rats allowed water ad libitum had a significantly lower level of hexobarbital metabolism than those deprived of water. Rats starved for 24 hr with or without water also had levels of hexobarbital metabolism significantly lower than their controls; with those animals allowed water ad libitum, the level was significantly lower than for those deprived of water. In vivo hexobarbital "sleeping time" experiments were in general agreement with these results. The in vitro metabolism of aniline was increased in both male and female rats following 24 hr starvation and in female rats (but not males) the effect was greater when water was allowed than when deprived. The differences between hydrated and dehydrated animals were not attributable to reduction in concentration of microsomal protein or the water content of liver. It is concluded that water consumption accentuates the effect of food deprivation on hepatic microsomal metabolism. 相似文献
390.
This article discusses the influence of welding process parameters on the content of delta ferrite in the claddings of AISI 317L, deposited onto IS: 2062 structural steel plate by the flux cored arc welding (FCAW) process. Measurement of delta ferrite within the cladding often gives important insight into the future mechanical and corrosion resistant behavior of the cladded structures. To predict and control the amount of residual ferrite, regression models were developed in terms of process parameters, using the data obtained from experiments. The experiments were conducted by using a central composite rotatable design of experiments. The study revealed that the cladding process parameters have influence over the formation of delta ferrite. 相似文献