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11.
Rotationally resolved resonant two-photon ionization (R2PI) spectra of ScCo and YCo are reported. The measured spectra reveal that these molecules possess ground electronic states of (1)Sigma(+) symmetry, as previously found in the isoelectronic Cr(2) and CrMo molecules. The ground state rotational constants for ScCo and YCo are B(0)(")=0.201 31(22) cm(-1) and B(0) (")=0.120 96(10) cm(-1), corresponding to ground state bond lengths of r(0) (")=1.812 1(10) A and r(0) (")=1.983 0(8) A, respectively. A single electronic band system, assigned as a (1)Pi<--X (1)Sigma(+) transition, has been identified in both molecules. In ScCo, the (1)Pi state is characterized by T(0)=15,428.8, omega(e)(')=246.7, and omega(e)(')x(e)(')=0.73 cm(-1). In YCo, the (1)Pi state has T(0)=13 951.3, omega(e)(')=231.3, and omega(e)(')x(e) (')=2.27 cm(-1). For YCo, hot bands originating from levels up to v(")=3 are observed, allowing the ground state vibrational constants omega(e)(")=369.8, omega(e)(")x(e)(")=1.47, and Delta G(12)(")=365.7 cm(-1) to be deduced. The bond energy of ScCo has been measured as 2.45 eV from the onset of predissociation in a congested vibronic spectrum. A comparison of the chemical bonding in these molecules to related molecules is presented. 相似文献
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With the online presence of more than half the world population, social media plays a very important role in the lives of individuals as well as businesses alike. Social media enables businesses to advertise their products, build brand value, and reach out to their customers. To leverage these social media platforms, it is important for businesses to process customer feedback in the form of posts and tweets. Sentiment analysis is the process of identifying the emotion, either positive, negative or neutral, associated with these social media texts. The presence of sarcasm in texts is the main hindrance in the performance of sentiment analysis. Sarcasm is a linguistic expression often used to communicate the opposite of what is said, usually something that is very unpleasant, with an intention to insult or ridicule. Inherent ambiguity in sarcastic expressions make sarcasm detection very difficult. In this work, we focus on detecting sarcasm in textual conversations from various social networking platforms and online media. To this end, we develop an interpretable deep learning model using multi-head self-attention and gated recurrent units. The multi-head self-attention module aids in identifying crucial sarcastic cue-words from the input, and the recurrent units learn long-range dependencies between these cue-words to better classify the input text. We show the effectiveness of our approach by achieving state-of-the-art results on multiple datasets from social networking platforms and online media. Models trained using our proposed approach are easily interpretable and enable identifying sarcastic cues in the input text which contribute to the final classification score. We visualize the learned attention weights on a few sample input texts to showcase the effectiveness and interpretability of our model. 相似文献
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Sreerama Rakesh Kumar N. Manoj Nukala Satheesh Kumar Sucharitha E. Ramya Babu H. Ramesh Narsimha Sirassu 《Russian Journal of General Chemistry》2021,91(12):2515-2521
Russian Journal of General Chemistry - This study is devoted to the efficient and practical synthesis of a novel series of pyrido[4,3-d]pyrimidine derivatives attached to 1,2,3-triazole ring and... 相似文献
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Dr. Elango Kumarasamy Sunil Kumar Kandappa Dr. Ramya Raghunathan Dr. Steffen Jockusch Prof. Jayaraman Sivaguru 《Angewandte Chemie (International ed. in English)》2017,56(25):7056-7061
Intramolecular atropselective aza Paternò–Büchi reaction involving atropisomeric enamide and imine functionalities under sensitized irradiation leads to azetidine products in good yield and selectivity (ee >96 %). A mechanistic model based on detailed photophysical and isomerization kinetic studies is provided that shed light into the reactivity of enamides leading to aza Paternò–Büchi reaction. 相似文献
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P.V. Sri Ramya Srinivas Angapelly Chander Singh Digwal Upasana Yadav Bathini Nagendra Babu Ahmed Kamal 《Journal of Saudi Chemical Society》2018,22(1):90-100
A simple and efficient protocol has been demonstrated for the preparation of densely functionalized 3-aroylimidazo[1,2-a]pyridines from 2-aminopyridines and chalcones using RuCl3·H2O/I2 catalytic system. The advantages, such as low catalyst loading, broad substrate scope with respect to substitutions on aminopyridines as well as chalcones, stability of heterocycles such as thiophene under the reaction conditions, operationally simple procedure and higher yields makes this approach remarkable for synthetic applications. 相似文献
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Sofia Trakhtenberg Ramya Kumar Jason Bianchini Savin Thor Debora M. Martino 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1311-1315
Photocrosslinking of thymine‐based water‐soluble polymer films was investigated at varying preparation conditions. Adding salt or decreasing the pH of the solution from which the films were cast resulted in the decreased efficiency of photoimmobilization, while increasing the pH was found to increase the photoimmobilization efficiency. A mechanistic rationale for the observed effects is proposed. 相似文献
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The galvanostatic polymerization of pyrrole is carried out on stainless steel electrodes using p-toluene sulphonic acid. The morphology of the film is studied from Scanning Electron Microscopy (SEM) measurements while
the nature of the substrate is analysed using Energy Dispersive X-ray Spectroscopy (EDAX) technique. The electrochemical behaviour
is studied using cyclic voltammetry, charge-discharge analysis and impedance spectroscopy. The feasibility of the electrode
for supercapacitor applications is investigated. The specific capacitance is estimated as ∼102 Farads per gram with 103 charge-discharge cycles. A plausible equivalent circuit for the system is proposed and the circuit parameters are obtained
by non-linear regression analysis. 相似文献
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Barry C. Pemberton Ramya Raghunathan Sabine Volla Jayaraman Sivaguru 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(39):12178-12190
Cucurbiturils are a family of molecular container compounds with superior molecular recognition properties. The use of cucurbiturils for supramolecular catalysis is highlighted in this concept. Both photochemical reactions as well as thermal transformations are reviewed with an eye towards tailoring substrates for supramolecular catalysis mediated by cucurbiturils. 相似文献