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1.
Back Cover: Spontaneous Stepwise Self‐Assembly of a Polyoxometalate–Organic Hybrid into Catalytically Active One‐Dimensional Anisotropic Structures (Chem. Eur. J. 31/2014) 下载免费PDF全文
2.
Aspartate‐Based CXCR4 Chemokine Receptor Binding of Cross‐Bridged Tetraazamacrocyclic Copper(II) and Zinc(II) Complexes 下载免费PDF全文
Randall D. Maples Amy N. Cain Dr. Benjamin P. Burke Dr. Jon D. Silversides Dr. Ryan E. Mewis Thomas D'huys Prof. Dominique Schols Prof. Douglas P. Linder Prof. Stephen J. Archibald Prof. Timothy J. Hubin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12916-12930
The CXCR4 chemokine receptor is implicated in a number of diseases including HIV infection and cancer development and metastasis. Previous studies have demonstrated that configurationally restricted bis‐tetraazamacrocyclic metal complexes are high‐affinity CXCR4 antagonists. Here, we present the synthesis of Cu2+ and Zn2+ acetate complexes of six cross‐bridged tetraazamacrocycles to mimic their coordination interaction with the aspartate side chains known to bind them to CXCR4. X‐ray crystal structures for three new Cu2+ acetate complexes and two new Zn2+ acetate complexes demonstrate metal‐ion‐dependent differences in the mode of binding the acetate ligand concomitantly with the requisite cis‐V‐configured cross‐bridged tetraazamacrocyle. Concurrent density functional theory molecular modelling studies produced an energetic rationale for the unexpected [Zn(OAc)(H2O)]+ coordination motif present in all of the Zn2+ cross‐bridged tetraazamacrocycle crystal structures, which differs from the chelating acetate [Zn(OAc)]+ structures of known unbridged and side‐bridged tetraazamacrocyclic Zn2+‐containing CXCR4 antagonists. 相似文献
3.
Petrus Zwart John Taylor Simon Morton Randall Cayford Gerald Fontenay Marc Allaire 《Synchrotron Radiation News》2015,28(2):22-27
The Berkeley Center for Structural Biology (BCSB) operates and develops a suite of protein crystallography beamlines at the Advanced Light Source (ALS) located at Lawrence Berkeley National Laboratory (LBNL). Although the ALS was conceived as a low-energy (1.9-GeV), third-generation synchrotron source of vacuum ultraviolet (VUV) and soft X-ray radiation, it was realized during the development of the facility in the mid-1990s that a multipole wiggler coupled with brightness-preserving optics would result in a beamline whose performance in the energy range of 5 to 15 keV would be sufficient for most protein crystallographic experiments. Later, the hard X-ray capabilities of the ALS were expanded by the addition of three superconducting bending magnets, resulting in additional protein crystallography facilities at the ALS [1]. 相似文献
4.
Randall Claywell Laszlo Nadai Imre Felde Sina Ardabili Amirhosein Mosavi 《Entropy (Basel, Switzerland)》2020,22(11)
The accurate prediction of the solar diffuse fraction (DF), sometimes called the diffuse ratio, is an important topic for solar energy research. In the present study, the current state of Diffuse irradiance research is discussed and then three robust, machine learning (ML) models are examined using a large dataset (almost eight years) of hourly readings from Almeria, Spain. The ML models used herein, are a hybrid adaptive network-based fuzzy inference system (ANFIS), a single multi-layer perceptron (MLP) and a hybrid multi-layer perceptron grey wolf optimizer (MLP-GWO). These models were evaluated for their predictive precision, using various solar and DF irradiance data, from Spain. The results were then evaluated using frequently used evaluation criteria, the mean absolute error (MAE), mean error (ME) and the root mean square error (RMSE). The results showed that the MLP-GWO model, followed by the ANFIS model, provided a higher performance in both the training and the testing procedures. 相似文献
5.
Mass spectral studies on 1‐n‐pentyl‐3‐(1‐naphthoyl)indole (JWH‐018), three deuterium‐labeled analogues and the inverse isomer 1‐naphthoyl‐3‐n‐pentylindole 下载免费PDF全文
6.
Sanjiban Chakraborty Yamil J. Colón Randall Q. Snurr SonBinh T. Nguyen 《Chemical science》2015,6(1):384-389
Porous organic polymers (POPs) possessing meso- and micropores can be obtained by carrying out the polymerization inside a mesoporous silica aerogel template and then removing the template after polymerization. The total pore volume (tpv) and specific surface area (ssa) can be greatly enhanced by modifying the template (up to 210% increase for tpv and 73% for ssa) as well as by supercritical processing of the POPs (up to an additional 142% increase for tpv and an additional 32% for ssa) to include larger mesopores. The broad range of pores allows for faster transport of molecules through the hierarchically porous POPs, resulting in increased diffusion rates and faster gas uptake compared to POPs with only micropores. 相似文献
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Jonathan B. Zung Randall L. Woodlee Ming-Ren S. Fuh Isiah M. Warner 《International journal of environmental analytical chemistry》2013,93(3-4):149-158
Abstract The use of multidimensional fluorescence for detecting the effects of select pollutants on algal fluorescence and production is demonstrated. Multidimensional fluorescence is ideally suited to rapidly measure algal fluorescence generated by both chlorophyll a and accessory pigments, as well as any changes induced by pollutants. Laboratory cultured and natural algae samples from classes Chlorophyceae, Bacillariophyceae, and Cyanophyceae were exposed to substituted nitroaromatics and fluorescence spectra of the algae recorded. Notable spectroscopic changes and fluorescence quenching were observed. In addition, a novel method for rapidly preconcentrating dilute natural marine samples is described. 相似文献
10.
The problem of chemical order of polyamide-hydrazides prepared from terephthaloyl chloride with an unsymmetrical monomer, p-aminobenzhydrazide, is discussed. An NMR method for identifying the molecular structure of species formed in the early stages of poly condensation has enabled the course of a polymerization to be followed during this time and the final degree of order to be predicted qualitatively. These studies have provided a demonstration that the structure of these polymers can be controlled to a significant degree by appropriate variations in experimental conditions. But even under the most adverse conditions usually employed, poly amide-hydrazides are found to be at least “partially ordered” copolymers. The techniques developed for this study may find application in the study of other polymer forming reactions with monomers having two functional groups with dissimilar reactivities. 相似文献