500 W rod-type 4 × 4 multicore ultrafast fiber laser.

We present a coherently combined femtosecond fiber chirped-pulse-amplification system based on a rod-type, ytterbium-doped, multicore fiber with 4 × 4 cores. A high average power of up to 500 W (after combination and compression) could be achieved at 10 MHz repetition rate with excellent beam quality. Additionally, < 500 fs pulses with up to 600 µJ of pulse energy were also realized with this setup.

An omics approach to rational feed: Enhancing growth in CHO cultures with NMR metabolomics and 2D-DIGE proteomics.

Expression of recombinant proteins exerts stress on cell culture systems, affecting the expression of endogenous proteins, and contributing to the depletion of nutrients and accumulation of waste metabolites. In this work, 2D-DIGE proteomics was employed to analyze differential expression of proteins following stable transfection of a Chinese Hamster Ovary (CHO) cell line to constitutively express a heavy-chain monoclonal antibody. Thirty-four proteins of significant differential expression were identified and cross-referenced with cellular functions and metabolic pathways to identify points of cell stress.

Profiling convoluted single-dimension proton NMR spectra: a Plackett-Burman approach for assessing quantification error of metabolites in complex mixtures with application to cell culture.

Single-dimension hydrogen, or proton, nuclear magnetic resonance spectroscopy (1D-(1)H NMR) has become an attractive option for characterizing the full range of components in complex mixtures of small molecular weight compounds due to its relative simplicity, speed, spectral reproducibility, and noninvasive sample preparation protocols compared to alternative methods. One challenge associated with this method is the overlap of NMR resonances leading to "convoluted" spectra. While this can be mitigated through "targeted profiling", there is still the possibility of increased quantification error.

Metastable β-Bi2O3 Nanoparticles with Potential for Photocatalytic Water Purification Using Visible Light Irradiation.

Photocatalytic studies under visible light irradiation using nanosized β-Bi2O3 are reported. β-Bi2O3 nanoparticles are prepared starting from the well-defined bismuth oxido cluster [Bi38O45(OMc)24(DMSO)9]⋅2 DMSO⋅7 H2O (OMc=O2CC3H5) using a straightforward hydrolysis and annealing protocol. Powder X-ray diffraction studies, transmission electron microscopy, diffuse reflectance UV/Vis spectroscopy and nitrogen adsorption measurements (using the Brunauer-Emmett-Teller (BET) theory) are used for the characterization of the as-prepared β-Bi2O3.

Copper(II) and triphenylphosphine copper(I) ethylene glycol carboxylates: synthesis, characterisation and copper nanoparticle generation.

Ethylene glycol-functionalised copper(II) carboxylates Cu[O2CCR2(OC2H4)nOCH3]2 (n = 0-3; R = H, Me) (2a-e) have been prepared by the reaction of [Cu2(OAc)4·2H2O] with CH3O(C2H4O)nCR2CO2H (1a-e). Upon reduction of 2a-e with triphenylphosphine, the corresponding tris(triphenylphosphine)copper(I) complexes 3a-e were obtained, which could be converted to the bis(triphenylphosphine)copper(I) complexes 4a-e by removal of one phosphine ligand. Based on IR spectroscopy and single crystal X-ray structure analysis the binding motif of the carboxylato group on the copper ion is discussed.

A straightforward approach to oxide-free copper nanoparticles by thermal decomposition of a copper(I) precursor.

The synthesis of the novel copper(I) precursor [Cu(PPh3)2(O2CCH2OC2H4OC2H4OCH3)] and its application in the straightforward solution synthesis of oxide-free copper nanoparticles by mere thermal decomposition are reported; depending on the precursor concentration particles of sizes of 10 nm or 30 nm are obtained in narrow size distributions.

Nonaqueous atomic layer deposition of aluminum phosphate.

Aluminum phosphate was deposited onto bundles of carbon fibers and flat glassy carbon substrates using atomic layer deposition by exposing them to alternating pulses of trimethylaluminum and triethylphosphate vapors. Energy dispersive X-ray spectroscopy (EDXS) and solid state nuclear magnetic resonance (SS-NMR) spectra confirmed that the coating comprises aluminum phosphate (orthophosphate as well as other stoichiometries). Scanning electron microscopic (SEM) images revealed that the coatings are uniform and conformal.

A convenient light initiated synthesis of silver and gold nanoparticles using a single source precursor.

A photochemical approach is reported for the straightforward synthesis of silver and gold nanoparticles using a single source precursor under very mild conditions.

Metastable β-Bi2O3 nanoparticles with high photocatalytic activity from polynuclear bismuth oxido clusters.

The synthesis of nanoscaled β-Bi(2)O(3) starting from the bismuth oxido clusters [Bi(6)O(4)(OH)(4)](NO(3))(6)·H(2)O, [Bi(22)O(26)(OSiMe(2)(t)Bu)(14)], [Bi(38)O(45)(NO(3))(20)(DMSO)(28)](NO(3))(4)·4DMSO and [Bi(38)O(45)(OMc)(24)(DMSO)(9)]·2DMSO·7H(2)O (OMc = O(2)CC(3)H(5)) under ambient conditions is reported. The metal oxido clusters are regarded as ideal precursors for β-Bi(2)O(3) due to their structural relationship with the latter. Nevertheless, different bismuth oxide polymorphs are accessible dependent on the hydrolysis protocol.

Au nanoparticles stabilised by PEGylated low generation PAMAM dendrimers: design, characterisation and properties.

The preparation and characterisation of a series of well-defined low generation (poly)amidoamine (PAMAM)-based dendrimers with end-grafted ethylene glycol ether moieties of type N(CH(2)CH(2)C(O)NHCH(2)CH(2)NR(2))(3) (3a, R=CH(2)CH(2)C(O)OCH(2)CH(2)OCH(3); 3b, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(2)C(2)H(5); 3c, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(9)CH(3)), [CH(2)N(CH(2)CH(2)C(O)NHCH(2)CH(2)NR(2))(2)](2) (4, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(2)C(2)H(5)) and (R(2)NCH(2)CH(2)NHC(O)CH(2)CH(2))N[CH(2)CH(2)N(CH(2)CH(2)C(O)NHCH(2)CH(2)NR(2))(2)](2) (5a, R=CH(2)CH(2)C(O)OCH(2)CH(2)OCH(3); 5b, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(2)C(2)H(5); 5c, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(9)CH(3)) and their application for the stabilisation of gold nanoparticles (Au NPs) is described. These dendrimers were prepared by a consecutive divergent synthesis methodology including Michael addition and amidation cycles. For comparison, amidoamine related model compounds N(C(3)H(7))R(2) (1, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(2)C(2)H(5)) and [CH(2)NR(2)](2) (2, R=CH(2)CH(2)C(O)O(CH(2)CH(2)O)(2)C(2)H(5)) were also synthesised to estimate the minimum required donating capabilities of the stabiliser.

Aging of rubrene layers in Ni/rubrene heterostructures studied by magneto-optical Kerr effect spectroscopy.

Magneto-optical Kerr effect (MOKE) spectroscopy was applied to probe the aging of Ni/rubrene bilayers under ambient atmosphere. A comparison between the simulated MOKE spectra of the heterostructure and the experimental MOKE spectra recorded at several time intervals after the samples were exposed to the ambient atmosphere demonstrates that the organic layer undergoes slow oxidation. The Ni top layer was found to exhibit capping properties, reducing the rate of oxidation of the organic underlayer in comparison with single organic layers.