Synthesis and characterization of [Cu(Phca2en)(PPh3)X] (X=Cl, Br, I, NCS, N3) complexes: crystal structures of [Cu(Phca2en)(PPh3)Br] and [Cu(Phca2en)(PPh3)I]

New mixed-ligand copper(I) complexes, [Cu(Phca₂en)(PPh₃)X], [Phca₂en = N,N′-bis(β-phenylci-nnamaldehyde)-1,2-diiminoethane and X=Cl (1), Br (2), I (3), NCS (4), N₃ (5)] have been synthesized and characterized by various techniques. ¹H and ¹³C-NMR and IR spectral data of these copper(I) complexes are compared with the free ligand to elucidate some structural features. The structures of [Cu(Phca₂en)(PPh₃)Br] (2) and [Cu(Phca₂en)(PPh₃)I] (3) have been determined from single-crystal data showing that the coordination geometry around copper atom is a distorted tetrahedron. Furthermore, these Cu(I) complexes exhibit supramolecular motifs of the type multiple phenyl embraces resulting from attractive interactions between phenyl rings of PPh₃ moieties. The presence of the C–H…Cu weak intramolecular hydrogen bonds, due to the trapping of C–H bonds in the vicinity of the metal atoms, is also reported.     

Ketoconazol‐Triiodide Ion Pair Complex as a Suitable Carrier in an Iodide Selective Membrane Electrode

A novel membrane sensor for selective monitoring of iodide, consisting of a triiodide‐ketoconazole ion pair complex dispersed in a PVC matrix, plasticized with a mixture of 2‐nitrophenyl octyl ether and dioctylphtalate with unique selectivity toward iodide ions, is described. The influence of membrane composition, pH of test solution and foreign ions on the electrode performance were investigated. The optimized membrane demonstrates a near‐Nernstian response for iodide ions over a wide linear range from 1.0 × 10^?2 to 1.0 × 10^?5 M, at 25 ± 1 °C. The electrode could be used over a wide pH range 3–10 and has the advantages of high selectivity, fast response time and good lifetime (over 4 months). It was successfully used as indicator electrode in potentiometric titrations and direct potentiometric assay of iodide ions.     

A simple colorimetric method for the assay of penicillin G salt and penicillamine by oxidation with iodate

A simple colorimetric procedure is described for determination of penicillin G salt and penicillamine. It is based on oxidation with potassium iodate at room temperature and measurement of the liberated iodine at 520 nm after extraction with carbon tetrachloride. Compared with other procedures, this method proved to be more rapid, highly reproducible and reasonably accurate. The relative standard deviation did not exceed 0.9% and 0.4% for penicillin and penicillamine, respectively. The procedure has been successfully applied to pharmaceutical preparations containing either of the two compounds.     

Development of a ~3He Gas Filling Station at the China Spallation Neutron Source

At the China Spallation Neutron Source(CSNS), we have developed a custom gas-filling station, a glassblowing workshop, and a spin-exchange optical pumping(SEOP) system for producing high-quality ~3He-based neutron spin filter(NSF) cells. The gas-filling station is capable of routinely filling ~3He cells made from GE180 glass of various dimensions, to be used as neutron polarizers and analyzers on beamlines at the CSNS. Performance tests on cells fabricated at our gas-filling station are conducted via neutron transmission and nuclear-magneticresonance measurements, revealing nominal filling pressures, and a saturated ~3He polarization in the region of 80%, with a lifetime of approximately 240 hours. These results demonstrate our ability to produce competitive NSF cells to meet the ever-increasing research needs of the polarized neutron research community.     

Linker engineering in metal–organic frameworks for dark photocatalysis

Dark reactions featuring continuous activity under light off conditions play a critical role in natural photosynthesis. However, most artificial photocatalysts are inactive upon the removal of the light source, and the artificial photocatalysts with dark photocatalysis abilities have been rarely explored. Herein, we report a Ti-based metal–organic framework (MOF), MIL-125, exhibiting the capability of dark photocatalytic hydrogen production. Remarkably, the introduction of different functional groups onto the linkers enables distinctly different activities of the resulting MOFs (MIL-125-X, X = NH₂, NO₂, Br). Dynamic and thermodynamic investigations indicate that the production and lifetime of the Ti³⁺ intermediate are the key factors, due to the electron-donating/-withdrawing effect of the functional groups. As far as we know, this is the first report on dark photocatalysis over MOFs, providing new insights into the storage of irradiation energy and demonstrating their great potential in dark photocatalysis due to the great MOF diversity.

A Ti-based MOF with long-lived Ti³⁺ can achieve dark photocatalysis. The different groups on the organic linker modulate electron storage ability and the lifetime of Ti³⁺, significantly regulating dark photocatalytic activity in H₂ production.     

Gamow Temperature in Tsallis and Kaniadakis Statistics

Relying on the quantum tunnelling concept and Maxwell–Boltzmann–Gibbs statistics, Gamow shows that the star-burning process happens at temperatures comparable to a critical value, called the Gamow temperature (T) and less than the prediction of the classical framework. In order to highlight the role of the equipartition theorem in the Gamow argument, a thermal length scale is defined, and then the effects of non-extensivity on the Gamow temperature have been investigated by focusing on the Tsallis and Kaniadakis statistics. The results attest that while the Gamow temperature decreases in the framework of Kaniadakis statistics, it can be bigger or smaller than T when Tsallis statistics are employed.     

High‐mobility solution‐processed zinc oxide thin films on silicon nitride

A high effective electron mobility of 33 cm² V^–1 s^–1 was achieved in solution‐processed undoped zinc oxide (ZnO) thin films. The introduction of silicon nitride (Si₃N₄) as growth substrate resulted in a mobility improvement by a factor of 2.5 with respect to the commonly used silicon oxide (SiO₂). The solution‐processed ZnO thin films grown on Si₃N₄, prepared by low‐pressure chemical vapor deposition, revealed bigger grain sizes, lower strain and better crystalline quality in comparison to the films grown on thermal SiO₂. These results show that the nucleation and growth mechanisms of solution‐processed films are substrate dependent and affect the final film structure accordingly. The substantial difference in electron mobilities suggests that, in addition to the grain morphology and crystalline structure effects, defect chemistry is a contributing factor that also depends on the particular substrate. In this respect, interface trap densities measured in high‐κ HfO₂/ZnO MOSCAPs were about ten times lower in those fabricated on Si₃N₄ substrates. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)

     

Current and frequency modulation characteristics for continuous-wave quantum cascade lasers at 9.06 μm

We report the characteristics of current induced frequency modulation (FM) for two continuous-wave quantum cascade lasers (QCLs) at 9.06 μm. Both the frequency tuning rate and the phase shift between intensity modulation and FM are measured at different modulation frequencies from 10 Hz to 200 kHz. The frequency tuning rate of the QCLs depends on both the modulation frequency and amplitude. The tested QCL has been used to detect ambient water vapor with wavelength modulation spectroscopy for validation with a numerical model.     

Vector and Cell Line Engineering Technologies Toward Recombinant Protein Expression in Mammalian Cell Lines

The rapid growth of global biopharmaceutical market in the recent years has been a good indication of its significance in biotechnology industry. During a long period of time in recombinant protein production from 1980s, optimizations in both upstream and downstream processes were launched. In this regard, one of the most promising strategies is expression vector engineering technology based on incorporation of DNA opening elements found in the chromatin border regions of vectors as well as targeting gene integration. Along with these approaches, cell line engineering has revealed convenient outcomes in isolating high-producing clones. According to the fact that more than 50% of the approved therapeutic proteins is being manufactured in mammalian cell lines, in this review, we focus on several approaches and developments in vector and cell line engineering technologies in mammalian cell culture.