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Experimental approaches and analytical technique for determining heavy metals in fallen dust at ferrosilicon production factory in Edfu, Aswan, Egypt
SOLTAN M.E., RAGEH H.M., RAGEH N.M., AHMED M.E.
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 2-.
https://doi.org/10.1631/jzus.2005.B0708
In this study aimed to evaluate the pollution extent of metals and nonmetals inside and outside the ferrosilicon production factory in Edfu, Aswan, Egypt, raw materials (quartz, cokes, iron oxides), ferrosilicon alloy, silica fume, dust and suspended dust (at different sites) samples were collected from the factory, and fallen dust samples were collected from outside the factory, horizontally (at different sites and different distance and directions) and vertically (at different floors in the selected buildings). Gravimetric methods, X-ray fluorescence (XRF), flame photometer, wide range carbon determinator and atomic absorption spectroscopy tools were used for elements determination. The results indicating that the fallen dust and its element contents on southern factory walls being higher than those on eastern factory walls may be due to the nature of the dusts and effects of wind force and wind direction. Fallen dust levels in different regions outside the factory were found to be affected by the distance, direction and floors. The nature of dust samples was affected by gravity and the suspended dust in different factory units depended on the work capacity and method of handling materials by personnel in different production units. Silica fume was a complicated problem, had dangerous effect against the workers’ health, and was characterized by high concentrations of SiO2 (90.6%~93.6%) and heavy metals (Mn, 420.6×10−6~520.3×10−6; Fe, 2354×10−6~2685×10−6; Co, 80.7×10−6~101.6×10−6 and Ni, 5.3×10−6~6.05×10−6). The TSP (Total Suspended Particulate) levels in all factory units were higher than the recommended air quality value (70 μg/m3) under Egyptian law. The effect of ferrosilicon factory fallen dust on the surrounding regions decreased with increasing distance between the factory and these regions. The suspended dust samples in the factory units and their components greatly exceeded national and international standards, so health and environmental criteria must be enforced on these units.
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Chemical shift assignments of two oleanane triterpenes from Euonymus hederaceus
HU He-jiao, WANG Kui-wu, WU Bin, SUN Cui-rong, PAN Yuan-jiang
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 3-.
https://doi.org/10.1631/jzus.2005.B0719
1H-NMR and 13C-NMR assignments of 12-oleanene-3,11-dione (compound 1) were completely described for the first time through conventional 1D NMR and 2D shift-correlated NMR experiments using 1H-1HCOSY, HMQC, HMBC techniques. Based on its NMR data, the assignments of 28-hydroxyolean-12-ene-3,11-dione (compound 2) were partially revised.
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Magnetic properties and heavy metal contents of automobile emission particulates
LU Sheng-gao, BAI Shi-qiang, CAI Jing-bo, XU Chuang
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 6-.
https://doi.org/10.1631/jzus.2005.B0731
Measurements of the magnetic properties and total contents of Cu, Cd, Pb and Fe in 30 automobile emission particulate samples indicated the presence of magnetic particles in them. The values of frequency dependent susceptibility (cfd) showed the absence of superparamagnetic (SP) grains in the samples. The IRM20 mT (isothermal remanent magnetization at 20 mT) being linearly proportional to SIRM (saturation isothermal remanent magnetization) (R2=0.901), suggested that ferrimagnetic minerals were responsible for the magnetic properties of automobile emission particulates. The average contents of Cu, Cd, Pb and Fe in automobile emission particulates were 95.83, 22.14, 30.58 and 34727.31 mg/kg, respectively. Significant positive correlations exist between the magnetic parameters and the contents of Pb, Cu and Fe. The magnetic parameters of automobile emission particulates reflecting concentration of magnetic particles increased linearly with increase of Pb and Cu content, showed that the magnetic measurement could be used as a preliminary index for detection of Pb and Cu pollution.
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Studies on the management of root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex of green gram, Vigna radiata cv ML-1108
HASEEB Akhtar, SHARMA Anita, SHUKLA Prabhat Kumar
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 7-.
https://doi.org/10.1631/jzus.2005.B0736
Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil, bavistin at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode, Meloidogyne incognita–wilt fungus, Fusarium oxysporum disease complex on green gram, Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants. Analysis of data showed that carbofuran and A. indica seed powder increased plant growth and yield significantly more in comparison to bavistin and P. fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus, A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens.
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Tea saponins affect in vitro fermentation and methanogenesis in faunated and defaunated rumen fluid
HU Wei-lian, WU Yue-ming, LIU Jian-xin, GUO Yan-qiu, YE Jun-an
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 13-.
https://doi.org/10.1631/jzus.2005.B0787
The effect of tea saponins (TS) on rumen fermentation and methane emission was examined using an in vitro gas production technique named Reading Pressure Technique. Three levels of TS addition (0, 0.2, 0.4 mg/ml) were evaluated in the faunated and defaunated rumen fluid. Compared to the control, TS addition decreased the 24 h gas production in the faunated rumen fluid, but had a minor effect on gas yield in the defaunated rumen fluid. The TS significantly reduced methane production in vitro. In the faunated rumen fluid, 0.2 or 0.4 mg/ml TS decreased the 24 h methane emission by 12.7% or 14.0%, respectively. Rumen fluid pH value was affected neither by TS addition nor by defaunation. The TS addition had only minor effects on volatile fatty acids, but the yield and pattern of volatile fatty acids were greatly affected by defaunation. While the molar proportion of acetate was not affected by defaunation, the propionate was significantly increased and the butyrate significantly decreased. Ammonia-N concentration and microbial protein yield were influenced by TS inclusion and defaunation. Inclusion of 0.4 mg/ml TS increased the microbial protein mass by 18.4% and 13.8% and decreased the ammonia-N concentration by 8.3% and 19.6% in the faunated and defaunated rumen fluid, respectively. Protozoa counts were significantly reduced by TS inclusion. The current study demonstrated the beneficial effect of TS on methane production and rumen fermentation, and indicated that this may be due to the effect of the associated depression on protozoa counts.
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Effects of supplementary urea‑minerals lick block on the kinetics of fibre digestion, nutrient digestibility and nitrogen utilization of low quality roughages
WU Yue-ming, HU Wei-lian, LIU Jian-xin
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 14-.
https://doi.org/10.1631/jzus.2005.B0793
Three yearling lambs with a rumen cannula were used to investigate the effects of supplementation with an urea-minerals lick block (ULB) on the kinetics of ruminal fibre digestion, nutrient digestibility and nitrogen (N) utilization of rice straw (RS), ammonia bicarbonate (AB)‑treated RS (ABRS) and hay prepared from natural pasture. The digestibility of dry matter and organic matter of RS increased by 13.1% and 12.7% (P<0.05) when the diet was supplemented with ULB, and approached to that of ABRS, indicating that the effect of ULB on digestibility of RS is similar to that of AB treatment. The digestibility of ABRS was slightly improved by the ULB feeding. Nitrogen retention was highest in lambs fed on ABRS alone, followed by hay with ULB, and was lowest in animals fed on RS with ULB. However, both the amount and proportion of N retention to N intake were enhanced by ULB supplementation to lambs fed on hay. The proportion of N retained to N digested decreased due to ULB supplementation to lambs fed on RS or ABRS. Supplementing ULB did not greatly influence the rumen degradation of either dry matter or crude protein in each of the three diets. RS and hay had similar values in the potential extent of digestion (PED) and digestion rate of PED (kd) of fibrous materials, but the discrete lag time for RS was lower than that for hay. The AB treatment significantly increased the PED (P<0.05) and kd (P<0.05) of RS. Neither the PED nor kd for RS and ABRS was influenced by ULB supplementation, but the kd for hay significantly increased due to ULB. The lag time for hay was also shortened by the ULB feeding. The ULB improved the digestion of fibre in the rumen of lambs fed on low quality roughage. It is inferred that while ULB is effective in increasing nutrient digestibility of low quality roughages by improving ruminal fibre digestion. A synchronized supply of N and energy to rumen microbes should be considered to improve the efficiency of N utilization when the basal diet is ammoniated straw.
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Isolation and physiological characteristics of a premature senescence mutant in rice (Oryza sativa L.)
LI Fu-zhen, JIN Song-heng, HU Guo-cheng, FU Ya-ping, SI Hua-min, JIANG De-an, SUN Zong-xiu
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 16-.
https://doi.org/10.1631/jzus.2005.B0803
A rice pse(t) (premature senescence, tentatively) mutant line, was isolated from 4 500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants (Zhonghua 11, japonica) at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 °C and 28 °C, respectively. The content of chlorophyll, soluble protein and MDA (malondialdehyde), net photosynthesis, the antioxidant enzyme activities of SOD (superoxide dismuase) (EC 1.15.1.1) and POD (peroxidase) (EC 1.11.1.7) and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant, the mutant showed the following characteristics: (1) Higher net photosynthesis rate (Pn) appeared in the 1st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1st leaf; (2) The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; (3) The symptom of premature senescence was accelerated in the mutant at 28 °C treatment. The MDA content and the SOD and POD activities between the 24 °C and 28 °C treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 °C treatment. The results show that pse(t) is sensitive to high temperature. The probable function of PSE(T) is discussed.
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Sequence analysis and expression pattern of MGTA1 gene in rice blast pathogen Magnaporthe grisea
WANG Jiao-yu, LIU Xiao-hong, LU Jian-ping, LIN Fu-cheng
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 18-.
https://doi.org/10.1631/jzus.2005.B0817
MGTA1, a putative fungal Zn(II)2Cys6 transcriptional activator-encoding gene, was isolated from rice blast pathogen Magnaporthe grisea, which is homologous to CLTA1 from Colletotrichum lindemuthianum with 51% identity at protein level. MGTA1 cassette contains a 2370 bp open reading frame, consisting of 6 exons, coding a 790 amino acid peptide. MGTA1 gene exists as a single copy in genomes of 7 strains of M. grisea, and is expressed in tip hyphae, conidia, and mature appressoria of strain Guy11.
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Partitioning and purification of extracellular β-1,3-1,4-glucanase in aqueous two-phase systems
HE Guo-qing, ZHANG Xiu-yan, TANG Xing-jun, CHEN Qi-he, RUAN Hui
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2005, 6( 8): 19-.
https://doi.org/10.1631/jzus.2005.B0825
The partition behaviors of β-1,3-1,4-glucanase, α-amylase and neutral proteases from clarified and whole fermentation broths of Bacillus subtilis ZJF-1A5 were investigated. An aqueous two-phase system (polyethylene glycol (PEG)/MgSO4) was examined with regard to the effects of PEG molecular weight (MW) and concentration, MgSO4 concentration, pH and NaCl concentration on enzyme partition and extraction. The MW and concentration of PEG were found to have significant effects on enzyme partition and extraction with low MW PEG showing the greatest benefit in the partition and extraction of β-glucanase with the PEG/MgSO4 system. MgSO4 concentration influenced the partition and extraction of β-glucanase significantly. pH had little effect on β-glucanase or proteases partition but affected α-amylase partition when pH was over 7.0. The addition of NaCl had little effect on the partition behavior of β-glucanase but had very significant effects on the partitioning of α-amylase and on the neutral proteases. The partition behaviors of β-glucanase, α-amylase and proteases in whole broth were also investigated and results were similar to those obtained with clarified fermentation broth. A two-step process for purifying β-glucanase was developed, which achieved β-glucanase recovery of 65.3% and specific activity of 14027 U/mg, 6.6 times improvement over the whole broth.
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14 articles
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