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Indole is an interesting molecule that exists in nature as a part of several important biomolecules including melatonin — a chemical that maintains the circadian rhythm in human body, serotonin — a chemical carrying messages through nerve cells, and tryptophan — an amino acid. It has a benzene ring fused with a pyrrole ring. Similar molecules containing cycloheptene ring fused with pyrrole — called azulene, cyclohepta[b]pyrrole and dihydrocyclohepta[b]pyrrole — also exist. It would be very interesting to see the effect on different properties of the above-mentioned biomolecules, if indole is replaced by azulene or cyclohepta[b]pyrrole or dihydro-cyclohepta[b]pyrrole. This paper precisely investigates such interesting substitutions. We replaced indole in the three biomolecules by azulene, cyclohepta[b]pyrrole, and dihydrocyclohepta[b]pyrrole and studied the corresponding change in acid-dissociation constant, static polarizabilities, first and second hyperpolarizabilities, absorption spectra, fluorescence, charge-transfer, and nature of the first two singlet, and the first two triplet states, using the state-of-the-art (time-dependent) density functional theory. The results are compared with the values obtained for the indole analogues calculated at the same level of theory.

The charge-transfer reaction of tetraarylbutatriene 1 with tetracyanoethene (TCNE) in dichloromethane at room temperature was studied and we found a novel addition reaction. A red crystalline material 2 was isolated as an intermediate product which is converted slowly into dihydronaphthalene derivative 3 in dichloromethane but rapidly in protic solvent. The structure of the compounds was determined by X-ray crystallography. The detailed structure and the plausible reaction mechanism have also been discussed.

Traditional mechanical keys are gradually replaced with touch keys. Capacitive touch keys have advantages in achieving higher sensitivity with a longer service life and lower cost. Hence, the capacitive touch key technology is widely used in consumer electronic products. In use of household electric appliances, such as electric kettle, induction cooker and exhaust hood, sometimes the water vapor would condense into visible moisture or even the water would splash out of the pot when overheated, which may lead to a falsely trigger of touch key. So, waterproof becomes a big challenge in household electric appliances. This paper analyzes how water affects capacitive touch key and proposes a waterproof capacitive touch key sensor interface circuit to overcome the challenge. Sensing of touch key capacitor would be influenced only when water covers more than two touch keys. Compensating channels working in certain strategy are used to decrease the influence of water. For the same water capacitor, the bigger threshold voltage, the bigger change of the counting number. A much smaller threshold voltage is better to further weak the effect of water. The circuit is implemented in a standard 110 nm CMOS process. The measured results show that the touch Signal to Noise and Water Disturb Ration (SNWDR) is 20.7 dB which proves that the proposed waterproof capacitive touch key sensor interface circuit is effective against water splash.

Two bis-tetraphenylporphyrin tweezers-like conjugates bearing different linkers have been characterized by means of electrochemical and photophysical methods. The thrust of this work was the complexation of these bis-porphyrins with C${}_{60}$ and metallic nitride endohedral fullerenes (MNEF) like Sc₃N@C${}_{80}$ in organic and in aqueus media — studied by a combination of steady-state and time-resolved spectroscopies. In the context of charge separation evidence for the formation of the 1a${}^{(•+)}$-Sc₃N@C${}_{80}^{(•-)}$ and 1c${}^{(•+)}$-Sc₃N@C${}_{80}^{(•-)}$ charge separated states in organic and aqueous media, respectively, came from transient absorption spectroscopy. Multi-wavelength analyses afforded charge separated state lifetimes of around 400 ps.