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651.
Biodiesel was synthesized from soybean oil by transesterification over Li2SiO3 catalyst.The Li2SiO3 can be used for biodiesel production directly without further drying or thermal pretreatment,no obvious difference in the FAME conversion(92.4-96.7%) between the air-exposed catalyst(24-72 h) and the fresh one(94.2%).This leads to important benefits when considering industrial applications of Li2SiO3 as a solid catalyst for storing and handling catalyst without taking special actions. 相似文献
652.
L.-C. Tung C.L. Yang D. Smirnov L.N. Pfeiffer K.W. West R.R. Du Y.-J. Wang 《Solid State Communications》2009,149(37-38):1531-1534
Submillimeter wave induced resistance oscillations in two ultra-high mobility GaAs/Al0.24Ga0.76As quantum well samples have been investigated by means of a backward wave oscillator and far-infrared laser at 3He temperatures. Subnikov–de Haas oscillation, submillimeter wave induced resistance oscillation, and magnetoplasmon resonance occur simultaneously in this frequency regime. The primary radiation induced resistance minimum shifts toward cyclotron resonance with increasing radiation frequency. The positions of these minima agree well with those of the magnetoplasmon resonance. The higher-order harmonics of the resistance oscillation remain around the multiples of the cyclotron resonance frequency. An in situ transmission measurement exhibits an asymmetric broadening of the cyclotron resonance, appearing as a combination of the cyclotron resonance and the magnetoplasmon resonance, but no features directly linked to the microwave induced resistance oscillation can be seen. 相似文献
653.
Synthesis of a Photostable Near‐Infrared‐Absorbing Photosensitizer for Selective Photodamage to Cancer Cells 下载免费PDF全文
Tung‐Sheng Hsieh Jhen‐Yi Wu Prof. Dr. Cheng‐Chung Chang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(31):9709-9715
A new class of near‐infrared (NIR)‐absorptive (>900 nm) photosensitizer based on a phenothiazinium scaffold is reported. The stable solid compound, o‐DAP, the oxidative form of 3,7‐bis(4‐methylaminophenyl)‐10H‐phenothiazine, can generate reactive oxygen species (ROS, singlet oxygen and superoxide) under appropriate irradiation conditions. After biologically evaluating the intracellular uptake, localization, and phototoxicity of this compound, it was concluded that o‐DAP is photostable and a potential selective photodynamic therapy (PDT) agent under either NIR or white light irradiation because its photodamage is more efficient in cancer cells than in normal cells and is without significant dark toxicity. This is very rare for photosensitizers in PDT applications. 相似文献
654.
James Tung 《Journal of Mathematical Analysis and Applications》2006,318(2):397-409
Analogues of the Hausdorff-Young and Hardy-Littlewood theorems are proved for functions in Fock spaces. Estimates of Taylor coefficients are shown to be sharp in the sense of Duren-Taylor. 相似文献
655.
Ling-Bao Xing Xiao-Jun Wang Xue-Wang Gao Bin Chen Chen-Ho Tung 《Supramolecular chemistry》2015,27(5-6):298-302
A new cationic amphiphile (1) functionalised with platinum(II) terpyridyl unit was designed and synthesised to realize self-assembly in water. Using UV–vis and emission spectroscopy, scanning electron microscopy, cryogenic transmission electron microscopy, dynamic light scattering and time-correlated single-photon counting technique, we have demonstrated that amphiphile 1 can self-assemble into stable vesicular aggregates upon direct dissolution in water, which is rarely observed in the literature. 相似文献
656.
Shear stress overshoot behavior was studied in four drilling fluid systems and ten bentonite dispersions. These overshoot properties, also described by the American Petroleum Institute as gel strengths, were measured after gelation times of 10 s to 24 h at temperatures of 20–80 °C. Two different rheometers were used to measure overshoot behavior. Gel strength development with time followed a first-order model. Gel development rates at 20 °C varied from 0.005 to 0.01 min–1 for drilling fluid systems and from 0.0004 to 0.02 min–1 for bentonite dispersions. Increasing the gelation temperature for each drilling fluid system caused an increase in the gelling rate constant. Comparison of gel strengths in bentonite dispersions were made using a Fann 35 A viscometer and a Weissenberg Rheogoniometer. Higher gel strength values observed using the Rheogoniometer were believed to be due to differences in instrument spring stiffness and fixture inertia. 相似文献
657.
Zhi Yong Bao Prof. Wei Zhang Dr. Yong‐Liang Zhang Jijun He Prof. Jiyan Dai Dr. Chi‐Tung Yeung Dr. Ga‐Lai Law Dr. Dang Yuan Lei 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(5):1303-1308
Detailed understanding of the interaction between a chiral molecule and a noble metal surface is essential to rationalize and advance interfacial self‐assembly of amino acids and metal‐mediated anchoring of proteins. Here we demonstrate that individual Au@Ag core–shell nanocuboids can serve as a plasmonic reporter of an extended helical network formed among chemisorbed cysteine molecules, through generating an interband absorption enhanced, Ag‐surface‐exclusive circular dichroism (CD) band in the UV region. The observed unusual, strong CD response in the hybrid Au@Ag–cysteine system can be used to probe in real time conformational evolution and structural rearrangement of biomolecules in general and also monitor the interfacial interaction between a metal surface and an adsorbed molecule, opening up the possibility of using Ag nanostructures as promising stereochemically attuned nanosensors. 相似文献
658.
Most of the research on integrated inventory and routing problems ignores the case when products are perishable. However, considering the integrated problem with perishable goods is crucial since any discrepancy between the routing and inventory cost can double down the risk of higher obsolescence costs due to the limited shelf-life of the products. In this paper, we consider a distribution problem involving a depot, a set of customers and a homogeneous fleet of capacitated vehicles. Perishable goods are transported from the depot to customers in such a way that out-of-stock situations never occur. The objective is to simultaneously determine the inventory and routing decisions over a given time horizon such that total transportation cost is minimized. We present a new “arc-based formulation” for the problem which is deemed more suitable for our new tabu search based approach for solving the problem. We perform a thorough sensitivity analysis for each of the tabu search parameters individually and use the obtained gaps to fine-tune the parameter values that are used in solving larger sized instances of the problem. We solve different sizes of randomly generated instances and compare the results obtained using the tabu search algorithm to those obtained by solving the problem using CPLEX and a recently published column generation algorithm. Our computational experiments demonstrate that the tabu search algorithm is capable of obtaining a near-optimal solution in less computational time than the time required to solve the problem to optimality using CPLEX, and outperforms the column generation algorithm for solving the “path flow formulation” of the problem in terms of solution quality in almost all of the considered instances. 相似文献
659.
Construction of a cryogen‐free thermal desorption gas chromatographic system with off‐the‐shelf components for monitoring ambient volatile organic compounds 下载免费PDF全文
Chang‐Feng Ou‐Yang Wei‐Cheng Liao Pei‐Chieh Wang Gang‐Jei Fan Chien‐Cheng Hsiao Ming‐Tung Chuang Chih‐Chung Chang Neng‐Huei Lin Jia‐Lin Wang 《Journal of separation science》2016,39(8):1489-1499
An automated gas chromatographic system aimed at performing unattended measurements of ambient volatile organic compounds was configured and tested. By exploiting various off‐the‐shelf components, the thermal desorption unit was easily assembled and can be connected with any existing commercial gas chromatograph in the laboratory to minimize cost. The performance of the complete thermal desorption gas chromatographic system was assessed by analyzing a standard mixture containing 56 target nonmethane hydrocarbons from C2–C12 at sub‐ppb levels. Particular attention was given to the enrichment efficiency of the C2 compounds, such as ethane (b.p. = –88.6°C) and ethylene (b.p. = –104.2°C), due to their extremely high volatilities. Quality assurance was performed in terms of the linearity, precision and limits of detection of the target compounds. To further validate the system, field measurements of target compounds in ambient air were compared with those of a commercial total hydrocarbon analyzer and a carbon monoxide analyzer. Highly coherent results from the three instruments were observed during a two‐month period of synchronized measurements. Moreover, the phenomenon of opposite diurnal variations between the biogenic isoprene and anthropogenic species was exploited to help support the field applicability of the thermal desorption gas chromatographic method. 相似文献
660.