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Donglei Wei Huili Li Chuanqing Yang Jianmin Fu Hou Chen Liangjiu Bai Wenxiang Wang Huawei Yang Lixia Yang Ying Liang 《Journal of polymer science. Part A, Polymer chemistry》2022,60(10):1588-1594
Acridone as a new kind of visible light photocatalyst has been developed to catalyze metal free atom transfer radical polymerization (ATRP). The photocatalyst possess low excited state potential as can undergo an oxidative quenching pathway to initiate ATRP of vinyl monomers. Kinetic study and light on/off reaction demonstrate the “living”/controlled nature of the polymerization by light. Block copolymers can be achieved by using PMMA as macroinitiator to reinitiate polymerization of other vinyl monomers, which shows highly preserved Br chain-end functionality in the synthesized polymers. Moreover, the polymerization can be conducted under air atmosphere as most photocatalysts need anaerobic condition, which may give inspiration of further application of this kind of photocatalyst. 相似文献
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We consider a multipath maximum flow problem introduced by Kishimoto (Networks 27(4)(1996)279-291). The focus is on efficient transformation from arc flows into multipath flows, where a multipath flow is a nonnegative combination of multipaths. A new algorithm that is more efficient than existing ones is proposed for the transformation. 相似文献
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Jin Wu Zhao Zhang Donglei Wang Shiming Liu Yongxin Tang Rongqing Tan Kuohai Zhang Chongyi Wan 《Optics & Laser Technology》2007,39(4):701-704
A novel long-pulse TE CO2 laser with UV-preionization is presented. With an active volume of 1.17 l and gas pressure of 30 kPa, the laser can discharge stably with low pulser energy and high sustainer energy. Various long-pulse discharges such as 12, 20 or 25 μs are demonstrated. At discharge pulse width of 23.9 μs, maximum output laser energy of 6.8 J is obtained at an efficiency of 9.0%. 相似文献
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Donglei Tang 《Chaos, solitons, and fractals》2011,44(7):538-547
We show how the symmetric Laplacian on p.c.f. self-similar sets, together with its associated Dirichlet form and harmonic functions, can be defined entirely in terms of average values of a function over basic sets. The approach combined the constructive limit-of-difference-quotients method of Kigami and the method of averages introduced by Kusuoka and Zhou for the Sierpinski carpet. We consider well-known examples, such as the unit interval, the Vicsek set,the hexagasket, and SG4. This paper has generalized the results in [11], [13] and [14], but a different proof is needed. 相似文献
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Graeme W. Carlile Robert A. Keyzers Katrina A. Teske Renaud Robert David E. Williams Roger G. Linington Christopher A. Gray Ryan M. Centko Luping Yan Suzana M. Anjos Heidi M. Sampson Donglei Zhang Jie Liao John W. Hanrahan Raymond J. Andersen David Y. Thomas 《Chemistry & biology》2012,19(10):1288-1299
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Computing semiparametric bounds for option prices is a widely studied pricing technique. In contrast to parametric pricing techniques, such as Monte-Carlo simulations, semiparametric pricing techniques do not require strong assumptions about the underlying asset price distribution. We extend classical results in this area. Specifically, we derive closed-form semiparametric bounds for the payoff of a European call option, given up to third-order moment (i.e., mean, variance, and skewness) information on the underlying asset price. We analyze how these bounds tighten the corresponding bounds, when only second-order moment (i.e., mean and variance) information is provided. We describe applications of these results in the context of option pricing; as well as in other areas such as inventory management, and actuarial science. 相似文献
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Donglei Sun Jiantao Fu Yinglin Lu Lijun Chen Hengliang Gong Huanhuan Zhao 《International journal of environmental analytical chemistry》2017,97(8):783-795
The neonicotinoid imidacloprid is a very important insecticide in maize cultivation in China. A laboratory experiment was conducted to investigate its absorption, transportation and distribution in maize plants. Plants were exposed to an aqueous solution of imidacloprid at five concentrations (10, 20, 50, 100 and 200 μg/mL). The residues of imidacloprid in different plant parts were determined by using a quick and effective method of high-performance liquid chromatography. Results showed that the average recoveries ranged from 85.16% to 102.23%, with relative standard deviations of 1.82–4.40% at three different spiking levels in each different matrix. The half-lives of imidacloprid in hydroponic maize water were from 5.33 to 11.55 days. The concentrations in roots, stems and leaves were from 5.61 to 7.48, 1.03 to 4.03 and 0 to 30.57 μg/mL after 6 h–7 days exposed in 10 μg/mL imidacloprid aqueous solutions, respectively. Our study showed that imidacloprid was strongly absorbed by roots and mainly accumulated in leaves. Quantity ratio and bioconcentration factors (BCFs) were also used to estimate the distribution and accumulation in maize. The values of quantity ratios were the highest in the leaves while lowest in the root after 7 days treatments, with the ranking of leaves > stem > root. The BCFs were 0.63–1.66, 0.52–0.92 and 3.20–6.78 in root, stem and leaves, respectively. These results demonstrated that the exposed time and imidacloprid application concentrations were also the main factors influencing the absorption. This study enhances our understandings of the uptake and distribution of imidacloprid in maize plants. 相似文献
8.
An HPLC method was developed for the determination of albendazole (ABZ) and its metabolites, a sulfoxide (ABZSO), a sulfone (ABZSO2), and albendazole-2-aminosulfone (ABZ-2-NH2SO2), from yellow perch muscle tissue with adhering skin. The muscle tissue samples were made alkaline with potassium carbonate and extracted with ethyl acetate, followed by a series of liquid-liquid extraction steps. After solvent evaporation, the residue was reconstituted in the initial mobile phase combination of the gradient. The mobile phase consisted of a buffer, 50 mM ammonium acetate (pH = 4.0) in 10% methanol-water, and 100% acetonitrile. The gradient was from 20% acetonitrile to 85% acetonitrile. The analytes were chromatographed on an RP Luna C18(2) column and detected by fluorescence with excitation and emission wavelengths of 290 and 330 nm, respectively. The average recoveries from fortified muscle tissue for ABZ (20-100 ppb), ABZ-SO (20-200 ppb), ABZSO2 (8-100 ppb), and ABZ-2-NH2SO2 (20-100 ppb) were 85, 95, 101, and 86%, respectively, with corresponding CV values of 9, 3, 6, and 4%, respectively. Their LOQ values were 10, 10, 1, and 10 ppb, respectively. The procedure was applied to determine ABZ and its major metabolites in the incurred muscle tissue of yellow perch obtained after orally dosing the fish with ABZ. 相似文献
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Back Cover: Solubility‐Parameter‐Guided Solvent Selection to Initiate Ostwald Ripening for Interior Space‐Tunable Structures with Architecture‐Dependent Electrochemical Performance (Angew. Chem. Int. Ed. 2/2018) 下载免费PDF全文