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991.
Heterodyned two-dimensional (2D) IR spectra often suffer from inaccurate pulse delays and phase drift. We report a passive method of correcting these two inaccuracies by using wedged optics for subfemtosecond pulse delay resolution and reference measurements for phase corrections. Our approach is easy to implement into existing 2D IR spectrometers and makes experiments requiring long-term phase stability possible, such as the collection of 3D IR spectra. 相似文献
992.
In recent years the Indian economy has achieved a rapid growth rate. However, one of the challenges facing the economy is the large energy supply that would be needed to sustain this growth path. Hence attaining energy efficiency is crucial for the economy. This paper examines the Indian manufacturing sector and utilizes a variant of the directional distance function to obtain comprehensive measures of performance of the major manufacturing states, given the joint goals of achieving energy conservation and output growth. The results of the empirical application reveal that given the prevailing technology, the average manufacturing firm across the states could reduce energy input and increase output simultaneously by an annual average of 3.84%, by improving technical efficiency. To accommodate a larger simultaneous increase in output and reduction in energy use, India should adopt superior technologies so as to shift the efficient frontier outward. 相似文献
993.
Subhajit Chakraborty Dr. Somen Nandi Dr. Kankan Bhattacharyya Dr. Saptarshi Mukherjee 《Chemphyschem》2019,20(23):3221-3227
In this work, we propose a new analysis of the time resolved emission spectra of a photo-acid, HA, pyranine (8-hydroxypyrene-1,3,6-trisulphonic acid, HPTS) based on time resolved area normalized emission spectra (TRANES). Presence of an isoemissive point in TRANES confirms the presence of two emissive species (HA and A−) inside the system in bulk water and inside a co-polymer hydrogel [F127, (PEO)100–(PPO)70–(PEO)100]. We show that following electronic excitation, the local pH around HPTS, is much lower than the bulk pH presumably because of ejection of proton from the photo-acid in the excited state. With increase in time, the local pH increases and reaches the bulk value. We further, demonstrate that the excited state pKa of HPTS may be estimated from the emission intensities of HA and A− at long time. The time constant for time evolution of pH is ∼630 ps in water, ∼1300 ps in F127 gel and ∼4700 ps in CTAB micelle. The location and local viscosity sensed by the probe is ascertained using fluorescence correlation spectroscopy (FCS) and fluorescence anisotropy decay. The different values of the local viscosity reported by these two methods are reconciled. 相似文献
994.
Singh Surya P. Mukherjee Soumavo Galindo Luis H. So Peter T. C. Dasari Ramachandra Rao Khan Uzma Zubair Kannan Raghuraman Upendran Anandhi Kang Jeon Woong 《Analytical and bioanalytical chemistry》2019,411(6):1297-1297
Analytical and Bioanalytical Chemistry - The authors would like to bring to the reader’s attention that the Clarke error grid plot presented in Fig. 3 was generated using codes... 相似文献
995.
Tuhin Patra Satobhisha Mukherjee Jiajia Ma Felix Strieth‐Kalthoff Frank Glorius 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(31):10624-10630
Despite significant progress in aliphatic decarboxylation, an efficient and general protocol for radical aromatic decarboxylation has lagged far behind. Herein, we describe a general strategy for rapid access to both aryl and alkyl radicals by photosensitized decarboxylation of the corresponding carboxylic acids esters followed by their successive use in divergent carbon–heteroatom and carbon–carbon bond‐forming reactions. Identification of a suitable activator for carboxylic acids is the key to bypass a competing single‐electron‐transfer mechanism and “switch on” an energy‐transfer‐mediated homolysis of unsymmetrical σ‐bonds for a concerted fragmentation/decarboxylation process. 相似文献
996.
The first catalytic enantioselective Michael addition of deconjugated butyrolactams to N-arylmaleimides is developed with the help of a bifunctional tertiary aminosquaramide catalyst. Unlike the widely explored and structurally related vinylogous nucleophile – deconjugated butenolides, deconjugated butyrolactams are found to be exclusively α-selective. The resulting highly substituted and densely functionalized products, bearing contiguous all-carbon quaternary and tertiary stereocenters, are formed in good yields with moderate diastereoselectivity and good to excellent enantioselectivity (up to 99:1 er). 相似文献
997.
Chiradeep Mukherjee Saradindu Panda Asish Kumar Mukhopadhyay Bansibadan Maji 《International Journal of Theoretical Physics》2018,57(7):2068-2092
The Quantum-dot Cellular Automata (QCA) is the prominent paradigm of nanotechnology considered to continue the computation at deep sub-micron regime. The QCA realizations of several multilevel circuit of arithmetic logic unit have been introduced in the recent years. However, as high fan-in Binary to Gray (B2G) and Gray to Binary (G2B) Converters exist in the processor based architecture, no attention has been paid towards the QCA instantiation of the Gray Code Converters which are anticipated to be used in 8-bit, 16-bit, 32-bit or even more bit addressable machines of Gray Code Addressing schemes. In this work the two-input Layered T module is presented to exploit the operation of an Exclusive-OR Gate (namely LTEx module) as an elemental block. The “defect-tolerant analysis” of the two-input LTEx module has been analyzed to establish the scalability and reproducibility of the LTEx module in the complex circuits. The novel formulations exploiting the operability of the LTEx module have been proposed to instantiate area-delay efficient B2G and G2B Converters which can be exclusively used in Gray Code Addressing schemes. Moreover this work formulates the QCA design metrics such as O-Cost, Effective area, Delay and Cost α for the n-bit converter layouts. 相似文献
998.
999.
A.K. Mukherjee 《Applied Surface Science》2009,255(12):6168-6172
The effect of periodic variation of external pressure on the catalytic oxidation of CO is simulated for a modified Ziff-Gulari-Barshad (ZGB) model including the Eley-Rideal (ER) step. The external CO partial pressure is periodically varied between its values in reactive and CO poisoned states. The results show different amplitudes of such perturbation significantly influence the CO2 production rate. Latter also changes with the period of such oscillations, especially for perturbations with larger amplitudes. However, for a given period there is a critical value of the amplitude above which, the catalyst surface becomes irreversibly poisoned. 相似文献
1000.
J.M.B. Shorto P.R.S. Gomes J. Lubian L.F. Canto S. Mukherjee L.C. Chamon 《Physics letters. [Part B]》2009
We propose a new technique to analyze total reaction cross sections. In this technique, which has been previously applied to fusion reactions, the experimental data are used to build a dimensionless reaction function, which does not depend on the system size or details of the optical potential. In this way, total reaction cross sections for different systems can be directly compared. We employ this technique to perform a systematic study of reaction cross sections of weakly bound systems in different mass ranges, and compare their reaction functions with the ones of tightly bound systems with similar masses. We show that breakup reactions and neutron transfers in halo systems lead to large reaction functions, well above the ones of typical tightly or weakly bound stable systems. 相似文献