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1.
An intact auditory system at birth is requisite for the successful accomplishment of many developmental skills. Evoked responses to auditory stimuli have been used as a sensitive test to determine the functional status of the adult and neonatal brain. It has been established that fetuses can hear in utero and respond to external acoustic stimuli. We present an overview of the transmission of sound through the maternal abdomen to the fetal ear and the recordings of an auditory evoked response obtained from the fetus using a non-invasive magnetoencephalography technique. The investigation of cortical activity of the fetus in response to auditory stimulation can help understand and track the neurological development of the fetus. 相似文献
2.
The reactions of the 3-methoxy-isoxazole quinones 1 and 9 in a highly polar solution of dimethyl sulfoxide have been studied. Quinones of type 2, 4/11, 5/12, 6 and 7/13 have been isolated; nmr measurements give a detailed insight into the reaction mechanism. 相似文献
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3-Methoxy[2, 1]benzisoxazole-4, 7-quinones 1 and naphth[2,3-c]isoxazole-4,9-quinone 4 react with dimethyl sulfoxides to give sulfoximidoquinones 2 and 5 , sulfimidoquinones 8 and 11 respectively as major products. 相似文献
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The rate of electron transfer from organic sulfides to [CrV(ehba)2]− (ehba-2-ethyl-2-hydroxy butyric acid) decreases with a decrease in the polarity of the medium. The anionic surfactant, SDS and the cationic surfactant, CTAB have different effects on the kinetics of this reaction. The micellar inhibition observed in the presence of SDS is probably due to the decrease in the polarity and the electrostatic repulsion faced by the anionic oxidant from the anionic micelle and the partition of the hydrophobic substrate between the aqueous and micellar phases. The micellar catalysis in the presence of CTAB is attributed to the increase in the concentration of both reactants in the micellar phase. This micellar catalysis is observed to offset the retarding effects of the less polar micellar medium and the unfavorable charge-charge interaction between the + charge developed on S center in the transition state and the cationic micelle. This catalysis is contrary to the enormous micellar inhibition observed with IO4−, HSO5− and HCO4− oxidation of organic sulfides. 相似文献
5.
Kwon Gu-Joong Bandi Rajkumar Yang Bong-Suk Park Chan-Woo Han Song-Yi Park Ji-Soo Lee Eun-Ah Kim Nam-Hun Lee Seung-Hwan 《Cellulose (London, England)》2021,28(14):9169-9185
Cellulose - Lignocellulose nanofibrils (LCNFs) were produced from the biomass of Mongolian oak for the first time using deep eutectic solvent pretreatment and mechanical defibrillation. Three... 相似文献
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Rajendran Arunachalam Eswaran Chinnaraja Arto Valkonen Kari Rissanen Palani S. Subramanian 《应用有机金属化学》2019,33(11)
The multidentate ligand H2 L upon complexation with Zn (II) and Cd (II) provide a one‐dimensional polymeric networks. These coordination polymers (CPs) CP‐1 and CP‐2 containing Zn (II) and Cd (II) metals respectively are well characterized. The single crystal structural analysis confirms the formation of one‐dimensional coordination polymer with zigzag fashion in CP‐1 and ladder chain CP‐2 . Both the CPs are applied as catalysts to synthesize various cyclic carbonates from epoxides and carbon dioxide. The catalysts are giving better conversion under solvent‐free and additive‐free condition using 10 bar CO2 and 100 °C as optimized pressure and temperature. The detailed kinetic experiments suggesting the first order kinetics, the energy of activation (Ea) is calculated for this catalytic conversion. 相似文献
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Arumugam Vasudevan Gayathri Devi Gurusamy Rajkumar Kathiresan Sakthipandi Venkatachlam Rajendran Nallaiyan Rajendran Mani Rajkumar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1434-1449
Abstract Phosphate-based bioactive glasses and their glass ceramics for 47P2O5– (30.5)CaO–(22.5 ? x)Na2O–xZrO2 for different ZrO2 contents (x = 0, 1.5, 3.0, 4.5, and 6.0 mol%) were prepared through melt quenching and controlled heat treatment procedures. The amorphous nature of glasses and the presence of crystalline phases in glass ceramics were studied by means of X-ray diffraction (XRD) studies. The density, molar volume, ultrasonic velocities, attenuation, elastic constants, and microhardness of glass and glass ceramics were used to study the structural changes. The formation of hydroxyapatite layer on the surface of glasses and glass ceramics after immersion in simulated body fluid (SBF) was explored through XRD, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) analyses. The results indicate that the added ZrO2 increases the crosslink density of glasses, resulting in network stability, and also induces the formation of an apatite layer on the surface of glasses. 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