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121.
122.
Fernand Dupire 《Fresenius' Journal of Analytical Chemistry》1959,170(1):317-326
Zusammenfassung Die Gaschromatographie bei hoher Temperatur kann mit Erfolg zur Analyse der Teerprodukte einschließlich der schwerflüchtigen Komponenten wie der Fünfringsysteme benutzt werden. Sie gestattet eine rasche Bestimmung der Zusammensetzung eines Teers oder eines Öls, was mit den herkömmlichen Methoden undenkbar war. So ist zu hoffen, daß sie einen wertvollen Beitrag zu einer besseren Kenntnis des Teers und seiner Derivate leistet, eine rasche und sichere Kontrolle industrieller Operationen erlaubt und neue Wege zu deren Vervollkommnung weist. 相似文献
123.
Shuai Liu Yujie Wu Teng Lin Robert Abel Jonathan P. Redmann Christopher M. Summa Vivian R. Jaber Nathan M. Lim David L. Mobley 《Journal of computer-aided molecular design》2013,27(9):755-770
Alchemical free energy calculations hold increasing promise as an aid to drug discovery efforts. However, applications of these techniques in discovery projects have been relatively few, partly because of the difficulty of planning and setting up calculations. Here, we introduce lead optimization mapper, LOMAP, an automated algorithm to plan efficient relative free energy calculations between potential ligands within a substantial library of perhaps hundreds of compounds. In this approach, ligands are first grouped by structural similarity primarily based on the size of a (loosely defined) maximal common substructure, and then calculations are planned within and between sets of structurally related compounds. An emphasis is placed on ensuring that relative free energies can be obtained between any pair of compounds without combining the results of too many different relative free energy calculations (to avoid accumulation of error) and by providing some redundancy to allow for the possibility of error and consistency checking and provide some insight into when results can be expected to be unreliable. The algorithm is discussed in detail and a Python implementation, based on both Schrödinger’s and OpenEye’s APIs, has been made available freely under the BSD license. 相似文献
124.
Photochromic Dithienylethene‐Containing Triarylborane Derivatives: Facile Approach to Modulate Photochromic Properties with Multi‐addressable Functions
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Dr. Chun‐Ting Poon Dr. Wai Han Lam Dr. Hok‐Lai Wong Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(5):2182-2192
A series of dithienylethene‐containing triarylboranes has been designed, synthesized, and characterized. The electrochemistry, photophysics, and photochromic behavior have also been studied. The photophysical and photochromic properties could be facilely tuned in this system by varying the thiophene spacers (thiophene, thienothiophene, and bithiophene) between the dithienylethene and the dimesitylboron (BMes2) or the position of the BMes2 substitution in the thiophene spacers. The absorption of closed form has been found to be more sensitive towards the structural modification upon incorporation of the BMes2 unit. Moreover, multi‐addressable photochromic reactivity is obtained upon addition of Lewis base (F?), which is due to the formation of boron–Lewis base adduct. The dependence of the photophysical and photochromic properties on the thiophene spacers and the position of the BMes2 substitution has been further supported by computational studies. 相似文献
125.
Vivian M. O. Carioni John D. Brockman Martha C. Morris Ruth A. Ngwenyama Lance A. Schell Vickie L. Spate Stacy Crane 《Journal of Radioanalytical and Nuclear Chemistry》2018,318(1):43-48
An INAA method for measurement of Se, Hg, Fe, Cr, Zn, Mn, K, and Br in autopsy cerebellum, anterior putamen, white matter, mid-frontal cortex, and inferior temporal lobe. Se, Hg, Fe, Cr, and Zn were measured autopsy samples collected from participants of the Memory and Aging Project. The first study examined the association between seafood consumption, brain Hg and Se, Apolipoprotein E (APOE-ε4) status, and brain neuropathology. Following the initial study, the samples were archived. A subsequent method was developed to measure Mn, K, and Br in the archived brain tissue samples. 相似文献
126.
The γ-radiation-initiated polymerization of acrylonitrile (AN) at 25[ddot] C has been studied, both in aqueous solution and in emulsion, at dose rates between 70 and 175 krad/hr. The effect of added emulsifier, sodium lauryl sulfate (SLS), on reaction rates, Rp, and on polymer molecular weight, Mn, has been investigated. G (monomer polymerized) values ranged from 7,500 in aqueous solution to 20,000 in bulk to 45,000 in emulsion, all based on the total energy absorbed. In the aqueous solution polymerization, where Rp is approximately first order in initial monomer concentration over the range 0.15 ± [AN]o ± 1.06 moles/liter, addition of SLS increases Rp but does not influence the order of the reaction with respect to [AN]o. In the emulsion system at 70 krad/hr and at a phase volume ratio AN/H2O of 1/2, (PR = 1/2), Rp varies as [SLS]0.1 over the concentration range 0.01 ± [SLS] ± 2.5± wt/vol of aqueous phase. At the same PR value, and at 80 krad/hr, Mn of the polymer (measured by viscometry in dimethylformamide solution) is effectively independent of [SLS] in the range of 0.01 ± [SLS] ± 10± wt/vol of aqueous phase. Initial Rp values are either independent of PR in the range 1/3 ± PR ± 1/1 or exhibit an insensitive and unsystematic dependence thereon. Based on measurements at 70 and at 175 krad/hr, the intensity exponent of Rp at PR = 1/2 is approximately 0.4. 相似文献
127.
Sammual Yu‐Lut Leung Elizabeth Suk‐Hang Lam Dr. Wai Han Lam Dr. Keith Man‐Chung Wong Prof. Dr. Wing‐Tak Wong Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(31):10360-10369
A new class of luminescent alkynylplatinum(II) complexes with a tridentate pyridine‐based N‐heterocyclic carbene (2,6‐bis(1‐butylimidazol‐2‐ylidenyl)pyridine) ligand, [PtII(C^N^C)(C?CR)][PF6], and their chloroplatinum(II) precursor complex, [PtII(C^N^C)Cl][PF6], have been synthesized and characterized. One of the alkynylplatinum(II) complexes has also been structurally characterized by X‐ray crystallography. The electrochemistry, electronic absorption and luminescence properties of the complexes have been studied. Nanosecond transient absorption (TA) spectroscopy has also been performed to probe the nature of the excited state. The origin of the absorption and emission properties has been supported by computational studies. 相似文献
128.
Elizabeth Suk‐Hang Lam Daniel Ping‐Kuen Tsang Dr. Wai Han Lam Dr. Anthony Yiu‐Yan Tam Dr. Mei‐Yee Chan Prof. Dr. Wing‐Tak Wong Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(20):6385-6397
A series of luminescent platinum(II) complexes of tridentate 1,3‐bis(N‐alkylbenzimidazol‐2′‐yl)benzene (bzimb) ligands has been synthesized and characterized. One of these platinum(II) complexes has been structurally characterized by X‐ray crystallography. Their electrochemical, electronic absorption, and luminescence properties have been investigated. Computational studies have been performed on this class of complexes to elucidate the origin of their photophysical properties. Some of these complexes have been utilized in the fabrication of organic light‐emitting diodes (OLEDs) by using either vapor deposition or spin‐coating techniques. Chloroplatinum(II)? bzimb complexes that are functionalized at the 5‐position of the aryl ring, [Pt(R‐bzimb)Cl], not only show tunable emission color but also exhibit high current and external quantum efficiencies in OLEDs. Concentration‐dependent dual‐emissive behavior was observed in multilayer OLEDs upon the incorporation of pyrenyl ligand into the Pt(bzimb) system. Devices doped with low concentrations of the complexes gave rise to white‐light emission, thereby representing a unique class of small‐molecule, platinum(II)‐based white OLEDs. 相似文献
129.
Duro V Décultot D Léon F Maze G 《The Journal of the Acoustical Society of America》2011,129(5):EL184-EL189
This paper is devoted to the study of acoustic vibrations induced by a flow upon an air-filled cylindrical tube vertically placed in water. A water pump with adapted piping generates a turbulent flow horizontally canalized in a large laboratory tank (6 m × 4 m × 3 m). The tube is located across this flow and an accelerometer measures vibrations. The signal processing performed on the recorded signals brings out resonance modes of the tube excited by the flow. A theoretical study (tube in air) and complementary experiments (tube in air and in water) are conducted to identify these modes. 相似文献
130.
The interaction of conjugated polyelectrolyte, PPE-SO(3)(-), with platinum(II) complexes, [Pt(tpy)(C≡CC(6)H(4)-CH(2)NMe(3)-4)](OTf)(2) (1) and [Pt(tpy)(C≡C-CH(2)NMe(3))](OTf)(2) (2), has been studied by UV-vis, and steady-state and time-resolved emission spectroscopy. A unique FRET from PPE-SO(3)(-) to the aggregated complex 1 on the polymer chain with Pt···Pt interaction has been demonstrated, resulting in the growth of triplet metal-metal-to-ligand charge transfer ((3)MMLCT) emission in the near-infrared (NIR) region. This two-component ensemble has been employed in a "proof-of-principle" concept for the sensitive and selective label-free detection of human serum albumin (HSA) by the emission spectral changes in the visible and in the NIR region. The spectral changes have been ascribed to the disassembly of the polymer-metal complex aggregates upon the binding of PPE-SO(3)(-) to HSA, which is rich in arginine residues and hydrophobic patches, leading to the decrease in FRET from PPE-SO(3)(-) to the aggregated platinum(II) complex. The ensemble is found to have high selectivity toward HSA over a number of polyelectrolytes, proteins and small amino acids. This has been suggested to be a result of the extra stabilization gained from the Pt···Pt and π-π interactions in addition to the electrostatic and hydrophobic interactions found in the polymer-metal complex aggregates. 相似文献