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Abstract  

The Mo–Fe/HZSM-5 catalyst was prepared by the impregnation method using citric acid to form Fe3+ and Mo6+ chelates in the impregnation solution. The structure, acidity and the catalytic performance for the macrolactonization of methyl 15-hydroxypentadecanoate to cyclopentadecanolide over Mo–Fe/HZSM-5 catalyst in comparison with unmodified HZSM-5, Fe/HZSM-5 and Mo/HZSM-5 catalysts were studied. The results indicate that the optimum ratio of Mo/Fe is 2.5. The Fe2(MoO4)3 and Al2(MoO4)3 species are formed on the Mo–Fe/HZSM-5 catalyst, with an increase of strength and slight diminution of the amount of acid sites. The Mo–Fe/HZSM-5 catalyst exhibited high activity for the selective macrolactonization of methyl 15-hydroxypentadecanoate to cyclopentadecanolide.

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Endophytic phosphorus- and potassium-solubilizing bacteria were screened from the root, rhizome, stem, and leaves of Moso Bamboo, and their diversity was analyzed using their 16S rDNA sequences. Twenty endophytic phosphorus and potassium-solubilizing bacteria were screened from 82 bamboo plants, among which the CT-B09-2, WYS-A01-1 and JL-B06 had higher activities in decomposing organophosphates. The three species showed a decomposition diameter/colony diameter (D/d) of 5.05, 4.19 and 2.95, respectively, and a solubilizing activity of 81.77 mg/L, 77.85 mg/L and 63.69 mg/L, respectively. JL-B06, WYS-A01-1 and CT-B09-2 had higher activities in decomposing inorganic phosphorus, with a decomposition diameter/colony diameter (D/d) of 2.34, 2.12 and 1.82, respectively, and a solubilizing activity of 30.58 mg/L, 38.89 mg/L and 48.35 mg/L, respectively. CT-B21, WYS-A03-1 and JL-B06 had higher activities in decomposing potassium, with a decomposition diameter/colony diameter (D/d) of 3.37, 4.84 and 4.33, respectively, and a solubilizing activity of 2.81 mg/L, 2.54 mg/L and 2.46 mg/L, respectively. The 16S rDNA sequence analysis showed that the 20 phosphorus- and potassium-solubilizing bacteria belong to 14 species from 10 genera, and mainly consist of Alcaligenes spp., Enterobacter spp. and Bacillus spp. Our results demonstrate the abundant diversity of endophytic phosphorus- and potassiumsolubilizing bacteria in Moso Bamboo.

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Abstract

In our previous work (Scientometrics 87:293–301, 2011), a numerical model of over-competitive research funding in “peer-group-assessed-grant-based-funding-system” was proposed and the process was firstly investigated quantitatively. The simulation results show that the mainstream of a very complicated research topic could obtain monopoly supremacy with only the aid of the mechanism the model described. Here, the numbers of publications of cosmology back to 1950 are utilized to empirically test this positive feedback mechanism. The development of three main theories of cosmology, Big Bang, Steady State and Plasma Universe, are revisited. The later two, which are non-mainstream opinions, both state in their peer reviewed papers, that their theories fit the phenomena that support the standard theory. The ratios of publications of the orthodox theory, Big Bang, approximately satisfy the numeric calculating results of our model. The reason for the discrepancy between the model and actual situation is discussed. A further question about the controversy is presented.

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Abstract

Except the alphabetic ordering authorship papers, the citations of multi-authored papers are allocated to the authors based on their contributions to the paper. For papers without clarification of contribution proportion, a function of author number and rank is presented to rightly determine the credit allocated proportion and allocated citations of each author. Our citation allocation scheme is between the equally fractional counting and the one using the inverse of author rank. It has a parameter to adjust the credit distribution among the different authors. The allocated citations can either be used alone to indicate one's performance in a paper, or can be applied in the modification of h-index and g-index to represent the achievement of a scientist on the whole. The modified h-index and g-index of an author makes use of more papers in which he or she played important roles. Our method is suitable for the papers with wide range of author numbers.

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Scientometrics
Authors:
Peng Hui Lv
,
Gui-Fang Wang
,
Yong Wan
,
Jia Liu
,
Qing Liu
, and
Fei-cheng Ma

Abstract

Graphene is a rising star as one of the promising materials with many applications. Its global literature increased fast in recent years. In this work, bibliometric analysis and knowledge visualization technology were applied to evaluate global scientific production and developing trend of graphene research. The data were collected from 1991 to 2010 from the Science Citation Index database, Conference Proceeding Citation Index database and Derwent Innovation Index database integrated by Thomson Reuters. The published papers from different subjects, journals, authors, countries and keywords distributed in several aspects of research topics proved that graphene research increased rapidly over past 20 years and boosted in recent 5 years. The distinctions in knowledge map show that the clusters distributed regularly in keywords of applied patents in recent 5 years due to the potential applications of graphene research gradually found. The analytical results provided several key findings of bibliometrics trend.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Kunbo Wang
,
Zhonghua Liu
,
Jian-an Huang
,
Donghe Fu
,
Fang Liu
,
Yushun Gong
, and
Xiaosong Wu

The potential of polyamide as adsorbent for separation of nine compounds — (±)-catechin (DL-C), (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECg), (−)-epigallocatechin gallate (EGCg), theaflavin (TF1), theaflavin 3-gallate (TF2A), theaflavin 3′-gallate (TF2B), and theaflavin 3,3′-digallate (TF3) — was studied. Polyamide TLC plates dried with a hair dryer, application as bands, and development in a horizontal chamber gave the best results. Detection was performed using iron(III) chloride-ethanol reagent. Twofold development with chloroform-methanol 2:3 ( v/v ) as mobile phase resulted in the separation of TF1, TF2A, TF2B, and TF3 from all the other compounds. EGCg, ECg, and EGC were separated but EC and DL-C were not separated from each other. The best mobile phase for each of the compounds is reported. The best separation of the five main catechins (EC, DL-C, EGC, ECg, and EGCg) was achieved by use of n -butanol-acetone-acetic acid 5:5:3 ( v/v ). In addition, separation of the flavonols myricetin, quercetin, kaempferol, and rutin and the phenolic acids gallic acid, chlorogenic acid, and caffeic acid was achieved by twofold development with chloroform-methanol 2:3 ( v/v ). The applicability of the method was checked by screening of extracts of green, black, oolong, and pu-erh tea.

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Abstract

A new composite catalytic system of Pd/C, 2,4,6-trichloro-[1,3,5]-triazine and N,N-dimethylformamide was investigated in nitrocyclohexane hydrogenation to ∊-caprolactam. The Pd/C catalyst was prepared by the incipient impregnation method and characterized by BET, N2 adsorption–desorption, XRD, TEM and H2 chemisorption. The results indicate that 2,4,6-trichloro-[1,3,5]-triazine plays a key role in one step synthesis of ∊-caprolactam from nitrocyclohexane hydrogenation. Besides ∊-caprolactam, the products include cyclohexanone oxime, cyclohexamine, cyclohexanone and cyclohexanol. A possible mechanism for nitrocyclohexane hydrogenation in 2,4,6-trichloro-[1,3,5]-triazine and N,N-dimethylformamide complex was proposed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Shen Shuifa
,
Li Yan
,
Shi Shuanghui
,
Gu Jiahui
,
Liu Jingyi
,
Fang Keming
, and
Zhou Jianzhong

Abstract  

The decay of 101Mo to levels in 101Tc has been studied using the three-parameter (--t) coincidence system of HpGe-HpGe detectors. According to the coincidence data, the decay scheme was modified. The positions of 221.80, 318.00, 377.90, 452.50, 515.42, 1011.05 and 1759.72 keV transitions have been arranged again, the transition positions of 104.70, 105.95 and 774.15 keV gamma-rays have been assigned for the first time, the positions of 169.00, 590.91, 980.52 and 1431.68 keV transitions have been reconfirmed, the 1508.01 keV gamma-ray was observed simultaneously for the first time and its transition position has been assigned. The -intensities and the values of log ft of most levels were calculated.

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Abstract

Mesoporous Ce0.8Zr0.2O2 oxides were prepared by a surfactant-assisted method of nanocrystalline particle assembly, and used as a support of nickel oxide nanocatalysts. The obtained mesoporous NiO/Ce0.8Zr0.2O2 nanocatalysts were characterized by XRD, N2 adsorption, TEM, H2-TPR and X-ray photoelectron spectroscopy techniques. The catalytic properties of the NiO/Ce0.8Zr0.2O2 nanocatalysts were evaluated by CO oxidation and toluene combustion. The results showed that the catalyst with 10 wt% NiO loading exhibited the highest catalytic activity for CO oxidation and toluene combustion.

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Abstract  

Two procedures are described for fast separations of berkelium from complex mixtures of reaction products arising from heavy ion reactions, such as18O+248Cm. The first procedure uses a combination of several extraction steps with a final separation on a cation exchanger, the second procedure starts with an anion exchange column which is followed by multiple extractions in different media. The elements separated in the different steps were analyzed and overall decontamination factors are given.

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