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911.
Suresh Chandra 《Pramana》2001,56(4):585-587
When observed spectrum of a diatomic molecule is expressed in terms of the Dunham coefficients Y
00, Y
10, Y
20, Y
01 and Y
11 only, dissociation energy of the molecule is given by Y
00+Y
10
2
/(−4Y
20). Kaur and Mahajan [1] have used the Dunham coefficients Y
10, Y
20, Y
01, and Y
11, for 15 vibrational states of 12 diatomic molecules (Y
00 is zero for the cases accounted for), but their dissociation energy cannot be reproduced by the expression Y
10
2
/(−4Y
20). Probable reason for the discrepancy has been discussed. 相似文献
912.
913.
Sandeep Mohanty Amrendra Kumar Roy Sandeep Reddy Kuchipudi Pavithran Vinay Kumar Arun Chandra Karmakar 《Phosphorus, sulfur, and silicon and the related elements》2016,191(6):857-866
We investigated the POCl3-mediated transformation of aromatic bisulfite adducts to the corresponding 5-arylidenethiazolidine-2,4-diones. The in situ transformation of an aromatic bisulfite adduct to the parent aldehyde in a non-aqueous non-polar solvent (toluene) was demonstrated using DoE (Design of experiment), offline 1H NMR, online ReactIR, HPLC, LC-MS, and GC-MS. By means of these analytical tools, we determined, for the first time, the structure of the intermediate species (aldehyde) prior to the carbon–carbon double-bond formation. The carbon–sulfur bond undergoes a fast cleavage, immediately after the addition of POCl3, which finally affords the corresponding 5-arylidenethiazolidine-2,4-diones. 相似文献
914.
Gokul Chandra Biswas Takahiro Watanabe Prof. Edwin T. Carlen Prof. Masatoshi Yokokawa Prof. Hiroaki Suzuki 《Chemphyschem》2016,17(6):817-821
A simple microfluidic valve, without any moving parts, is presented that can control solution flow on demand in microchannels of many different materials using a low‐power electric signal. Many independently operating valves can easily be integrated into complex microfluidic systems. The valve consists of a self‐assembled monolayer (SAM) formed on a platinum electrode that is incorporated directly in the microchannel. The normally‐on valve stops the solution flow due to a hydrophobic SAM on the electrode surface. The solution is allowed to pass the valve by applying a potential to the electrode, which removes the SAM due to reductive desorption. The valve operation is highly stable and has switching times of the order of 1 s. The valve is ideal for controlled solution manipulation in integrated micro‐analytical systems and autonomous microfluidic systems. 相似文献
915.
Chandra S Kumar R 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(1-3):518-525
Nickel(II) complexes of the general composition Ni(L)X(2) (where X=SCN, NO(3) and 1/2SO(4) and ligands=L(1) L(2) and L(3)) have been synthesized and characterized by elemental analyses, magnetic moments, IR, (1)H NMR, (13)C NMR and electronic spectral studies. Nickel(II) ions, such as nitrates, thiocyantes and sulphates were found to act as templates for the cyclic condensations [1+1] and [2+2] of NH(2--)C(6)H(4)--O--CH(2)--CH(2)--O--C(6)H(4)--NH(2), NH(2)--(CH(2))(2)--NH(2) and NH(2)--CH(CH(3))--CH(2)--NH(2) with C(6)H(5)--CO--CO--C(6)H(5), C(6)H(5)--CO--CH(2)--CO--C(6)H(5) and (COOH--CH(2)--CH(2))(2)S. All the complexes show magnetic moments corresponding to two unpaired electrons except [Ni(L(1))](NO(3))(2) and [Ni(L(2))](NO(3))(2) complexes which are diamagnetic. Electronic spectroscopy was used to analyse the differences between the paramagnetic and diamagnetic forms. Electrochemical properties have been studied extensively for Ni(III/II) and Ni(II/I) couples. The equilibrium between the paramagnetic and diamagnetic forms and the nickel(III/II) couple are strongly dependent on the electrolyte. It has been observed that the sulphate group coordinated selectively on the apical position of the nickel(II) centers of the compounds. The structural and electrochemical studies suggest that cooperative effects, involving coordination of sulphate to one nickel center, is responsible for the recognition of this anion. Various ligand field parameters have been calculated and discussed. 相似文献
916.
Raymond E. Borg Maryam Hatamimoslehabadi Stephanie Bellinger Jeffrey La Farha Mithila Chandra Yelleswarapu Jonathan Rochford 《Photochemistry and photobiology》2019,95(1):280-292
The synthesis, photophysical and photoacoustic characterization for a series of nine π‐extended quadrupolar curcumin dyes is presented. A systematic evaluation of the π‐bridging unit including the p‐phenyl, naphth‐4‐yl, thien‐2‐yl and hybrid 4‐naphthathien‐2‐yl groups is presented. Furthermore, evaluation of the strongly donating donor‐π‐acceptor‐π‐donor quadrupolar dimethylamino terminated derivatives is also included. Select dyes exhibit excited state absorption at increased laser fluence which translates to the production of a nonlinear enhanced photoacoustic response. In particular, the bis‐4‐dimethylaminonaphtha‐2‐thien‐5‐yl curcuminBF2 contrast agent DMA‐5 exhibits an excellent molar photoacoustics (PA) emission at both low (9.4 × 103 V M?1) and high (1.47 × 105 V M?1) laser fluence which is confirmed by its strong contrast by photoacoustic tomography (PAT). In summary, the strong absorbance and enhanced photoacoustic properties of naphthyl and thienyl curcuminoids here presented provides great promise for future photoacoustic imaging applications as demonstrated by preliminary PAT studies. 相似文献
917.
Md Murshed Bhuyan Hirotaka Okabe Yoshiki Hidaka Nirmal Chandra Dafader Nazia Rahman Kazuhiro Hara 《高分子科学杂志,A辑:纯化学与应用化学》2018,55(4):369-376
The objective of the work is to synthesize pectin-N, N-Dimethylacrylamide (DMAA) hydrogel by gamma radiation without using any initiators and cross-linking agents. Effect of radiation doses on gel fraction and equilibrium swelling as a function of pH were studied, and 5 kGy radiation dose was found to be the optimum dose for hydrogel synthesis. The grafting /crosslinking was investigated by Fourier transform infrared spectroscopy. Thermal properties and surface morphology were studied by differential scanning calorimetry and scanning electron microscopy. To study the drug release kinetics, 5-fluorouracil was loaded into the hydrogel and in vitro release was carried out in simulated gastric and intestinal fluid. The release profile of drug showed that more than 90% of the loaded drugs were released after 4 hours at both gastric fluid and intestinal fluid pH. Drug release data was fitted into zero order, Higuchi and Korsmeyer-Peppas kinetic models. Higuchi model was found to be the best fitted and release exponent ‘n’ value of Korsmeyer-Peppas model indicated the non-Fickian transport. 相似文献
918.
One‐Step Electrodeposition of NiCo2S4 Nanosheets on Patterned Platinum Electrodes for Non‐Enzymatic Glucose Sensing 下载免费PDF全文
Dr. Padmanathan Karthick Kannan Dr. Chunxiao Hu Prof. Dr. Hywel Morgan Dr. Chandra Sekhar Rout 《化学:亚洲杂志》2016,11(12):1837-1841
The preparation of NiCo2S4 (NCS) nanosheets on photolithographically patterned platinum electrodes by electrodeposition was explored. The as‐prepared nanosheets were systematically characterized by field‐emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy techniques. The NCS‐modified Pt electrode was used as a non‐enzymatic glucose sensor. The sensor response exhibited two linear regions in glucose concentration, with a limit of detection of 1.2 μm . The sensors showed that the as‐prepared NCS nanosheets have excellent electrocatalytic activity towards glucose with long stability, good reproducibility, and excellent anti‐interference properties, and thus, this material holds promise for the development of a practical glucose sensor. 相似文献
919.
The title compound [Ni(CPDD)(H2O)2]2(H 2O )2, {]Ni2(C44H28N8O12)] (H2O)2 }, where CPDD = 1H‐cyclopenta(2,1‐b:3,4‐b')(dipyridine‐2,5‐dione) has been prepared and its crystal structure determined by single crystal X‐ray diffraction at room temperature. The complex crystallizes in the triclinic space group P1 w ith two molecules in the asymmetric unit. The cell dimensions are a=10.452(1),b=14.098(1) & c=16.023 Å; D=110.13(1), E=100.63(1) & J=100.85(1)°. The two independent molecules in the asymmertic unit are related by pseudo two fold symmetry. In both the molecules the coordination environment around the Ni(II) may be best described as a distorted octahedral. Due to some delocalization of charge towards one of the oxygens(O1a) from the O2a atom some degree of bond localization has been observed. The individual diones of both the molecules are almost right angles at the metal atom. A long the y‐axis inversion related molecules are forming pseudo‐dimers through hydrogen bonding. 相似文献
920.