A novel heteroditopic terpyridine-pincer ligand as building block for mono- and heterometallic Pd(II) and Ru(II) complexes

A palladium-catalyzed Stille coupling reaction was employed as a versatile method for the synthesis of a novel terpyridine-pincer (3, TPBr) bridging ligand, 4'-{4-BrC6H2(CH2NMe2)(2)-3,5}-2,2':6',2 ''-terpyridine. Mononuclear species [PdX(TP)] (X = Br, Cl), [Ru(TPBr)(tpy)](PF6)(2), and [Ru(TPBr)(2)](PF6)(2), synthesized by selective metalation of the NCNBr-pincer moiety or complexation of the terpyridine of the bifunctional ligand TPBr, were used as building blocks for the preparation of heterodi- and trimetallic complexes [Ru(TPPdCl)(tpy)](PF6)(2) (7) and [Ru(TPPdCl)(2)]-(PF6)(2) (8). The molecular structures in the solid state of [PdBr(TP)] (4a) and [Ru(TPBr)(2)](PF6)(2) (6) have been determined by single-crystal X-ray analysis. Electrochemical behavior and photophysical properties of the mono-and heterometallic complexes are described. All the above di- and trimetallic Ru complexes exhibit absorption bands attributable to (MLCT)-M-1 (Ru -> tpy) transitions. For the heteroleptic complexes, the transitions involving the unsubstituted tpy ligand are at a lower energy than the tpy moiety of the TPBr ligand. The absorption bands observed in the electronic spectra for TPBr and [PdCl(TP)] have been assigned with the aid of TD-DFT calculations. All complexes display weak emission both at room temperature and in a butyronitrile glass at 77 K. The considerable red shift of the emission maxima relative to the signal of the reference compound [Ru(tpy)(2)](2+) indicates stabilization of the luminescent (MLCT)-M-3 state. For the mono- and heterometallic complexes, electrochemical and spectroscopic studies (electronic absorption and emission spectra and luminescence lifetimes recorded at room temperature and 77 K in nitrile solvents), together with the information gained from IR spectroelectrochemical studies of the dimetallic complex [Ru(TPPdSCN)(tpy)](PF6)(2), are indicative of charge redistribution through the bridging ligand TPBr. The results are in line with a weak coupling between the {Ru(tpy)(2)} chromophoric unit and the (non)metalated NCN-pincer moiety

Effect of Strain on Ferroelectric Field Effect in Strongly Correlated Oxide Sm0.5Nd0.5NiO3

We report the effect of epitaxial strain on the magnitude and retention of the ferroelectric field effect in high quality PbZr0.3Ti0.7O3 (PZT)/3.8-4.3 nm Sm0.5Nd0.5NiO3 (SNNO) heterostructures grown on (001) LaAlO3 (LAO) and SrTiO3 (STO) substrates. For SNNO on LAO, which exhibits a first-order metal-insulator transition (MIT), switching the polarization of PZT induces a 10 K shift in the transition temperature TMI, with a maximum resistance change between the on and off states of Δ/on ~75%. In sharp contrast, only up to 5% resistance change has been induced in SNNO on STO, where the MIT is second-order, with the modulation of TMI negligibly small. We also observe thermally activated retention of the off state resistance Roff in both systems, with the activation energy of 22 meV (28 meV) for devices on LAO (STO). The time dynamics and thermal response of the field effect instability points to phonon-assisted interfacial trapping of charged mobile defects, which are attributed to strain induced oxygen vacancies. At room temperature, Roff stabilizes at ~55% and ~19% of the initial switching levels for SNNO on LAO and STO, respectively, reflecting the significantly different oxygen vacancy densities in these two systems. Our results reveal the critical role of strain in engineering and modeling the complex oxide composite structures for nanoelectronic and spintronic applications

Pengaruh Variasi Tegangan dan Waktu Terhadap Kekerasan Lapisan Nikel dengan Metode Electroplating pada Coran Aluminium scrap

Abstrak Aluminium banyak digunakan dalam dunia industri karena sifatnya yang ringan, ketahanan korosi yang baik serta konduktivitas panas dan listrik yang tinggi. Kekerasannya yang tidak begitu tinggi dan penampilan yang kurang menarik perlu diperbaiki, yang salah satunya dengan melapisi aluminium dengan Nikel melalui proses electroplating. Penelitian ini bertujuan untuk mengetahui pengaruh tegangan dan waktu pelapisan Nikel pada pengecoran aluminium scrap. Spesimen terbuat dari coran velg bekas dengan ukuran 30 mm x 30 mm x 10 mm . Aluminium dilapisi Nikel dengan proses electroplating dengan tegangan 3 volt, 4,5 volt, dan 6 volt. Dengan variasi waktu pelapisan 5, 10 dan 15 menit. Setelah dilapisi, dilakukan pengujian kekerasan mikro dengan metode pengujian Vickers dengan beban 10 gr dan ditahan 10 s. Hasil pengujian menunjukan adanya kenaikan  nilai kekerasan pelapisan nikel seiring dengan meningkatnya tegangan listrik dan waktu. Pada tegangan listrik 3 volt sebesar 10,4 % - 15,9 %, tegangan listrik 4,5 volt sebesar 4,62 % - 14,3 %, dan tegangan listrik 6 volt sebesar 24,8 % - 84,2 %

Synthesis and self-assembly of giant porphyrin discs

Contains fulltext : 13852.pdf (publisher's version ) (Open Access

Protocol: Personality assessment as a support for referral and case-work in treatment for substance use disorders (PASRC-study)

<p>Abstract</p> <p>Background</p> <p>Assessment of co-morbid personality disorders in substance use disorders may lead to important insights concerning individual patients. However, little is known about the potential value of routine personality disorder assessment in a clinical context.</p> <p>Methods</p> <p>Patients are adults with past-year substance dependence seeking treatment at a centralized intake unit for substance abusers in the City of Copenhagen. A randomized controlled trial of assessment of personality disorders and individual feedback vs. a general life situation interview. Patients are followed at 3 and 6 months post-treatment</p> <p>Discussion</p> <p>If routine personality assessment improves outcomes of substance abuse treatment, the clinical implication is to increase the use of personality disorder assessment in substance abuse treatment settings.</p> <p>Trial registration</p> <p>Current controlled trials ISRCTN39851689</p