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Abstract  

A recent extensive review of research in British universities has produced a research rating for each university department based primarily on peer review of the department's publications. In this preliminary study, we compare these ratings with publication and citation data for the chemistry departments at two British universities. The results underline the importance of the most productive researchers in departments. This point is supported by citation data from a chemical engineering department.

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Abstract  

Thermal, chemical and rheological properties of ultraviolet aged asphalt binder were characterized by differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) and dynamic shear rheometer (DSR), respectively. Asphalt binder samples were made with different film thickness (50, 100, 200 and 500 μm) and suffered different ageing time (0, 48, 96 and 144 h), at a certain UV radiant intensity of 20 w m–2 in a self-made accelerated ageing oven. The results indicate that the UV light ageing would lead to the improvement of thermal behavior and the growth of the glass transition temperature of asphalt binder. This type of ageing can be also reflected from the FTIR spectra in terms of the characteristic peaks of the carbonyl groups and sulphoxides. The UV light ageing can change some rheological parameters of asphalt binder, such as complex modulus and phase angle. The ageing degrees of asphalt binder by this type of ageing test are mainly related to the ageing time and film thickness of the sample.

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Abstract  

Uniformly carbon-covered alumina (CCA) was prepared via the carbonisation of sucrose highly dispersed on the alumina surface. Using special thermogravimetry and sorptometry methods physicochemical properties of carbon-covered alumina surfaces were investigated. A numerical and analytical procedure for the evaluation of total heterogeneous properties (desorption energy distribution and pore-size distribution functions) on the basis of liquid thermodesorption from the sample surfaces under the quasi-equilibrium conditions are presented. The desorption energy distribution was derived from the mass loss Q-TG and the differential mass loss Q-DTG curves of thermodesorption of pre-adsorbed polar and apolar liquid films. For the first time, the evaluation of the fractal dimensions of carbon-covered alumina using the sorptometry, thermogravimetry and AFM data is presented.

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Abstract  

In this paper, the thermogenesis and differential scanning calorimetry (DSC) curves of energy release of the mitochondria isolated from variant strains of cytoplasmic male sterile lines of rices have been determined by using an LKB2277 Bioactivity Monitor and a DuPont 910 differential scanning calorimeter. The regularity and characteristics of the energy release of the mitochondria at constant and changing temperature were investigated, the differences in shape of the curves and the thermodynamic and kinetic characteristics of the thermogenesis of the mitochondria were compared, the thermodynamic and kinetic parameters of energy release of the mitochondria in the thermogenesis increasing stage were calculated, and the experimental thermokinetic equations describing the different thermogenesis processes were established.

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Prorocentrum donghaiense caused large-scale red tides off Chinese coast in recent years. Expressed sequence tag (EST) analysis was carried out for this dinoflagellate in order to identify the genes involved in its proliferation and death. A cDNA library was constructed for P. donghaiense at late exponential growth phase, and 308 groups of EST were generated, which include 36 contigs and 272 singletons. Among 22 groups showed homologies with known genes, 2 matched significantly with caspase and proliferating cell nuclear antigen. Caspase and proliferating cell nuclear antigen are 2 key proteins involved in programmed cell death. Their identification evidenced preliminarily the induction of PCD in aging P. donghaiense. The identified included also calmodulin and protein phosphatase, two proteins involved in diverse cell processes including PCD by binding to or modifying others.

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Epimedium pubescens Maxim. and Epimedium koreanum Nakai. are two common and confused species of Herba Epimedii in Chinese Pharmacopoeia 2010 edition. Different species and growing conditions lead to chemical differences between the two species which may result in the improper clinical usage. In this work, a new method based on rapid-resolution liquid chromatography combined with time-of-flight mass spectrometry (RRLC/TOFMS) has been developed for identification and differentiation of major flavonoids in two kinds of Epimedium extract and rat plasma. The compounds were identified effectively based on the accurate extract masses and formulae acquired by RRLC/TOFMS. The fragmentation rules deduced by collision-induced dissociation (CID) were successfully implemented in distinguishing some of the isomers, further validating the results. By using the combined analytical techniques, a total of 40 major flavonoids in extracts of two kinds of Epimedium were identified within 30 min, including 31 common components and 9 characteristic components. After oral administration, three prototype compounds in rat plasma were detected by comparing the constituents measured in vitro with those in vivo, and five metabolites were identified by contrasting the fragmentation rules. The identification and structural elucidation of the chemical constituents provided essential data for further pharmacological and clinical studies on different species of Epimedium.

Open access
Cereal Research Communications
Authors:
N. Niu
,
Y.X. Bai
,
S. Liu
,
Q.D. Zhu
,
Y.L. Song
,
S.C. Ma
,
L.J. Ma
,
X.L. Wang
,
G.S. Zhang
, and
J.W. Wang

Studies of the pollen abortion mechanism in thermo-sensitive male sterile lines may provide a strong foundation for breeding hybrid wheat and establishing a theoretical basis for marker-assisted selection. To investigate the cause of pollen abortion in Bainong thermo – sensitive male sterile (BNS) lines, we analyzed the properties of pollen grains, changes in the tapetum and microspores in different anther developmental stages, and the distribution and deposition of nutrient substances in microspores. We found that tapetum degraded in the early uninucleate stage in sterile BNS (S-BNS), which was earlier than that of fertile BNS (F-BNS) tapetum. Large amounts of insoluble polysaccharides, lipids, and proteins were deposited until the trinucleate pollen stage in the nutritive cells in F-BNS. At the binucleate stage, the vacuoles disappeared and pollen inclusion increased gradually. At the trinucleate stage, these nutrients would help pollen grains mature and participate in fertilization normally. Therefore, early degradation of the tapetum, which inhibits normal microspore development, and the limited content of nutrient substances in pollen may be the main factors responsible for male sterility in BNS lines.

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