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1

Kinetics and thermodynamics of heavy metal Cu(II) adsorption on mesoporous silicates

100%

Ge P. , Li F.

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nr 2

EN

Investigations were conducted to study the adsorption behavior of heavy metal Cu(II) on the mesoporous silicate SBA-15 (CONH₂-SBA-15) in aqueous medium by varying parameters such as contact time, temperature, ionic strength, and competing ions. Heavy metal adsorption was broadly independent of initial metal concentration. Competing ions in the aqueous solution had a small effect on the adsorption of Cu(II) on CONH₂-SBA-15. The adsorption data for Cu(II) fit well with the Langmuir and Redlich-Peterson models. Kinetic studies showed that the kinetic data are well described by the pseudo second-order kinetic model. Initial adsorption rate increases with an increase in temperature. The intraparticle diffusion model was the best in describing the adsorption kinetics for the Cu(II) on CONH₂-SBA-15. Thermodynamic analysis indicates that the adsorption is spontaneous and endothermic.

2

Winter bed-site selection by red deer Cervus elaphus xanthopygus and roe deer Capreolus capreolus bedfordi in forests of northeastern China

85%

Chen H. , Li F. , Luo L. , Wang H. , Ma J. , Li F.

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1999

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tom 44

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nr 2

EN

Winter bedding sites used by red deer Cervus elaphus xanthopygus Milne-Edwards, 1867 and roe deer Capreolus capreolus bedfordi Thomas, 1908 were studied in the forests of northeastern China from 1991 to 1992. Night beds used by both cervids were higher in canopy closure than day beds. Roe deer selected night bedding sites with denser canopy closure and higher percentage of coniferous trees, and day beds with better concealment cover than red deer. Roe deer selected night beds with higher canopy closure during cold mid winter period than during early and late winter period, whereas no such difference existed in day beds. Red deer showed no significant difference in canopy closure over day and night beds between mid and late winter. Canopy closure, composition of coniferous species, average distance to the nearest tree, and ground cover were identified to discriminate night and day beds for both cervids. The difference in selection of bed-site may reflect different energy requirements of large-bodied red deer and small-bodied roe deer.

3

Synthesis of modified mesoporous materials and comparative studies of removal of heavy metal from aqueous solutions

80%

Ge P. , Li F. , Zhang B.

Polish Journal of Environmental Studies

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2010

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tom 19

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nr 2

301-308

EN

The functionalized mesoporous’ potential ability of binding heavy metals using different templates, namely cetyltrimethylammonium (CTAB) (adsorbent A) and triblock copolymer (Pluronic P123, EO20PO70EO2O, Mav = 5800) (adsorbent B), was evaluated. The synthesized materials were characterized by powder X-ray diffraction (XRD), nitrogen gas sorption, FT-IR and solid-state ¹³C and ²⁹Si NMR spectroscopy and thermogravimetry (TGA) measurements. In the adsorption experiment, the effects of several variables (stirring time, pH and presence of other metals in the medium) were studied. On the basis of these results, it was observed that the adsorption capacities were higher for adsorbent B than adsorbent A. The results also confirmed that the ureido group (CO-NH₂) has a good affect of binding metal ion.

4

Research and development of Multi-Agent System based agile collaborative design system for machining centre

80%

Li F. , Chen N. , Zhou L.

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tom Vol. 31, nr 2

518-525

EN

Purpose: Today we face a demands always quickly varied market. For the machine tools manufacturers, reducing the development cycle of a product to be modified is much meaningful, and meanwhile, they have to improve (at least keep) the new machines performance. Consequently, an assistant-software has a certain degree of intelligent ability will have more advantages to improve the design quality and short design cycle simultaneously. Design/methodology/approach: The development of machine tools is a typical work of a distributed cooperative process supported by CAX. MAS (Multi-Agent system) is now the mainstream of contemporary studies on distributed intelligent software system, and can provide a foundation for the establishment of such system. Findings: In this paper, a MAS-based agile collaborative development system for MC (Machining Center) was set up using JADE (Java Agent DEvelopment framework). The whole system was divided into several functional modules that can carry out its typical mission. By taking the intelligent collaborative design module as an example, the configuration of Agents society was expatiated particularly. This module can provide intellectualized conceptual design help for MC designers. Research limitations/implications: Whereas, the other modules of this system have not been established, so in order to make it more perfect, some interfaces are left for the next expansion of other modules. Practical implications: A development process supported by this system for a customer ordered MC is taken to execute the prototype case study. According to the customer order information, three feasible proposals that have the greatest similarity are presented by the intelligent reasoning of CADDesignerAgents. By performing the parametric design and intelligent optimization, 3D dynamic MC model which is the customer satisfied is proposed and shown. Originality/value: The platform supported with those intelligent abilities has shown that it is a powerful tool on the MC family design for shorten the development cycle and improve the design quality.

5

Growth responses and non-structural carbohydrates in three wetland macrophyte species following submergence and de-submergence

80%

Qin X. , Li F. , Chen X. , Xie Y.

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nr 07

EN

We investigated the responses of growth and non-structural carbohydrates to submergence and de-submergence in three wetland macrophyte species. Survival rate, recovery ability, and soluble sugar and starch contents of flood-tolerant Polygonum hydropiper and of flood-sensitive Phalaris arundinacea and Carex argyi from Dongting Lake wetlands were investigated after 20, 40, and 60 days of complete submergence without light and 10 days after de-submergence. Plant dry weight and soluble sugar and starch contents decreased in all species during the submergence period. The decreases were slowest in P. hydropiper, intermediate in C. argyi, and most rapid in P. arundinacea. After 60 days of submergence, survival rates were 100, 50, and 0 % in P. hydropiper, C. argyi, and P. arundinacea, respectively. After recovery, plant dry weight increased in P. hydropiper and in C. argyi, but decreased in P. arundinacea. Compared to pre-submergence, soluble sugar contents generally increased and then remained relatively constant after recovery in all species, while starch content increased in P. hydropiper and decreased in P. arundinacea with increasing submergence time. For C. argyi, starch content decreased after recovery from the 20-day submergence, but increased after recovery from the 40- and 60-day submergences. These data illustrate mechanisms behind the flood tolerance of P. hydropiper and the sensitivity to flooding in P. arundinacea and C. argyi. These mechanisms include lower consumption and quicker accumulation of non-structural carbohydrates in flood-tolerant plants.

6

Effects of unstable elements with different hardness on lower limb loading

80%

Li F. , Mei Q. , Gu Y.

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tom Vol. 17, no. 2

85--92

EN

Purpose: Osteoarthritis of the knee is one of the most common diseases. For this chronic disease, modified footwear structure can effectively prevent and relieve disease of the knee. The aim of this study was to explore the effects of shoe surface elastic modulus on external knee adduction moment and ground reaction force and foot loading characteristics. Methods: Sixteen healthy female volunteers were recruited, and each subject performed five walking trials under two shoes condition. The lower limb loading data was collected using force platform and in-sole pressure measurement system. Results: The results showed that the external knee adduction moment was decreased in all stance phase when wearing SS (unstable shoes with soft unstable elements), compared with HS (unstable shoes with hard unstable elements). The ground reaction force showed no obvious change under two shoes condition. Additionally, compared with HS, plantar pressure transferred from medial foot to lateral foot when wearing SS. Along with changes of contact areas, average pressure and impulse had also presented this tendency. Conclusions: These results can provide some scientific evidence and suggestions for footwear companies, and for the foot plantar medial injury disease has also certain applicability.

7

The determination and correlation of various virulence genes, ESBL, serum bactericidal effect and biofilm formation of clinical isolated classical Klebsiella pneumoniae and hypervirulent Klebsiella pneumoniae from respiratory tract infected patients

71%

Shah R. K. , Ni Z. H. , Sun X. K. , Wang G. Q. , Li F.

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nr 4

EN

Klebsiella pneumoniae strains that are commonly recognized by clinicians and microbiologists are termed as classical K. pneumoniae (cKP). A strain with capsule-associated mucopolysaccharide web is known as hypervirulent K. pneumoniae (hvKP) as it enhances the serum resistant and biofilm production. Aim is to determine and correlate various virulence genes, ESBL, serum bactericidal effect and biofilm formation of clinical isolated cKP and hvKP from respiratory tract infected patients. A total of 96 K. pneumoniae strains were isolated from sputum of respiratory tract infected patients. The isolates were performed string test, AST, ESBL virulence gene, serum bactericidal and biofilm assays. Out of 96 isolates, 39 isolates (40.6%) were identified with hypervirulent phenotypes. The number of cKP exhibiting resistance to the tested antimicrobials and ESBLs were significantly higher than that of the hvKP strains. The virulence genes of K. pneumoniae such as K1, K2, rmpA, uge, kfu and aerobactin were strongly associated with hvKP than cKP. However, no significant difference was found in FIM-1 and MrKD3 genes. ESBL producing cKP and hvKP were significantly associated with strong biofilm formation (both P < 0.05) and highly associated with bactericidal effect of serum (both P < 0.05) than cKP strains. However, neither biofilm formation nor bactericidal effect of serum was found with significant difference in between ESBL producing cKP and ESBL producing hvKP strains (both P > 0.05). Although the hvKP possess more virulence gene, but they didn’t show any significant difference between biofilm formation and bactericidal effect of serum compared with ESBL producing cKP strains.

8

Potato waste treatment by microbial fuel cell. Evaluation based on electricity generation, organic matter removal and microbial structure

71%

Du H. , Li F. , Huang K. , Li W. , Feng C.

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tom Vol. 43, nr 1

5--18

EN

The performance of microbial fuel cell (MFC) in treating potato waste was evaluated using a two-chamber MFC supplied with potato liquid after mastication of market available fresh potato. Evaluation was conducted based on electricity generation, organic matter removal (CODCr, DOC and volatile fatty acids (VFAs)), and microbial structure on the anode and in the anodic solution of the reactor. Current density exhibited a trend that followed the concentration changes of organic matter in the solution, with its highest value being observed as 208 mA/m2. Effective removal of organic matter was also observed. By the end of the experiment, the removal for total COD reached about 84%. Bacterial structure analysis based on PCR, DGGE and sequencing indicated that more species were developed in the anodic solution than on the anode, with Proteobacteria, Firmicutes and Bacteroides being dominant. Geobacter, a well reported exoelectrogenic species, was found more predominant on the anode than in the anodic solution. The results thus indicated that simultaneous stabilization and electricity generation could be achieved when potato waste is treated in MFC.

9

Experimental study of herbaceous structure effects on reducing nutrient loss

61%

Gao C. , Cheng J. , Li F. , Zhang H. , Yang F. , Dai J.

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nr 3

EN

The objective of this study was to evaluate nutrient loss under herbaceous cover in simulated field conditions and quantify the influences of the aerial and underground parts of plants in preventing nutrient loss. The experimental settings were as follows: two herbs, i.e., alfalfa (Medicago sativa L.) and green foxtail (Setariaviridis (L.) Beauv.); four covers for each herb (0, 20-30%, 50-60%, and 80-90%); and two treatments (reserving the entire plant and trimming the aerial part of the plant). Through simulated rainfall, runoff and sediment samples were collected at the end of the soil tank and analysed for nitrogen (N) and phosphorus (P). The results indicated that nutrient loss gradually decreased with the increasing plant coverage, and the nutrient loss on the green foxtail slope was lower than that on the alfalfa slope under the same coverage. Although the effect of the alfalfa canopy on nutrient loss prevention was higher than that of the green foxtail, the capacity of the green foxtail root for conserving nutrients is stronger than that of alfalfa due to a different herbaceous plant leaf area index and root morphology distribution. An exponential function was found to characterize the different plant root length densities and nutrient losses on the slope.

10

A high-efficiency, two-dimensional gel electrophoriesis platform for mature leavs of grass pea (Lathyrus sativus L.)

51%

Wu Q. , Li C. , Ke L. , Jiao C. , Jiang J. , Sun X. , Li F. , Wang C.

Acta Physiologiae Plantarum

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2011

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tom 33

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nr 6

EN

Grass pea (Lathyrus sativus L.) is the most drought-tolerant legume crop rich in dietary protein. However, little is known about the molecular mechanisms of its drought resistance. Two-imensional gel electrophoresis (2-DE) is an important experiment technique in proteomics, which has been applied extensively in studies on plant resistance to abiotic stress. To establish an effective 2-DE platform and further study the droughtresistance mechanisms of grass pea using proteomic approaches, three protein extraction methods, different isoelectric focusing (IEF) conditions and various types of gel strips were evaluated using mature leaves. The results showed that the trichloroacetic acid (TCA)/acetone protein extraction method, extending time at low voltage for IEF and using 18 cm gel strip with pH 4.0–7.0 were optimum conditions for 2-DE analysis of grass pea leaves. Applying these optimized 2-DE conditions, 1,481 total protein spots were detected in control leaves and 1,346 spots in polyethylene glycol -treated leaves, of which 67 differentially expressed protein spots were obtained relative to the control. These data suggested that an efficient 2-DE platform with high repeatability and resolution for grass pea mature leaves had been established for the first time here, which could be further used to investigate the droughtresistance molecular mechanisms of grass pea.

11

Enhanced magnetoelastic performance in Pr/Mn-doped Laves phase (Tb,Ho)Fe2 compounds

51%

Wang M. K. , Liu J. J. , Lv X. J. , Ding Q. L. , Li F. , Pan Z. B. , Xia W. X. , Du J.

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2020

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tom Vol. 38, No. 4

707--714

EN

Magnetostrictive TbxHo0.8−xPr0.2Fe1.8Mn0.1 (0 ⩽ x ⩽ 0.20) alloys are prepared by arc-melting and subsequent annealing. The dopant of Pr/Mn introduced into RFe2 compounds effectively stabilizes the forming of single C15 Laves phase at ambient pressure. The easy magnetization direction (EMD) varies when Tb content increases, which is accompanied by a crystalstructural transition. EMD lies along ‹1 0 0› axis for x ⩽ 0.05, rotating to ‹1 1 1› axis for x ⩽ 0.12, with a tetragonal symmetry changing to a rhombohedral one. Magnetocrystalline-anisotropy compensation is obtained with the optimized composition of x = 0.12, shifting to the Tb-poor side in comparison to Pr/Mn-free counterpart. An enhanced effect on magnetoelastic properties is achieved in Tb0.12Ho0.68Pr0.2Fe1.8Mn0.1, which simultaneously possesses a low anisotropy and high magnetostriction performance, i.e. λs ~ 420 ppm, λ111 ~ 970 ppm, and a large low-field λa ~ 390 ppm/2 kOe, being 30 % higher than that of Pr/Mn-free compound. Combining low-cost light rare earth Pr with the lower Tb content, Tb0.12Ho0.68Pr0.2Fe1.8Mn0.1may make it promising solution in magnetostrictive applications.

12

Genome-wide association study of body weight in Wenshang Barred chicken based on the SLAF-seq technology

51%

Li F. , Han H. , Lei Q. , Gao J. , Liu J. , Liu W. , Zhou Y. , Li H. , Cao D.

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nr 3

13

The relationship between liver dysfunction and arsenic methylation in Mice

41%

Li S. , Ma R. , Niu Q. , Xu S. , Pang L. , Ding Y. , Mu L. , Jing M. , Feng G. , Liu J. M. , Wang H. , Li F. , Guo S.

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nr 4

EN

The different methyl metabolic products of inorganic arsenic lead to various toxicities. Arsenic has been demonstrated to induce hepatotoxicity by oxidative stress. The relationship between hepatic injury and inorganic methylation is not yet known. This study was designed to explore the relationship between arsenic methylation and liver oxidative stress induced by arsenic trioxide (ATO). Forty healthy KM mice were randomly divided into control group (0.9% saline) and As₂O₃ (1.0 mg/Kg/day, 2.0 mg/Kg/day, 4.0 mg/Kg/day) groups with gastric perfusion for five weeks using high-efficiency liquid chromatography and hydride genesis atomic fluorescence spectroscopy (HPLC-HGAFS). The products of arsenic trioxiode methylating, including trivalent inorganic arsenic (iAs³⁺), pentavalent inorganic arsenic (iAs⁵⁺), mono methyl arsenic (MMA), and dimethyl arsenic (DMA) in the liver were determined. The indexes of arsenic methylation, including primary methyl index (PMI) and second methyl index (SMI) were calculated. The level of hepatic function and activity of MDA, GSH, SOD, and TAOC were detected with kits. We found that the remaining arsenic metabolic products in liver significantly increased with the increasing doses of arsenic trioxide and the liver function and oxidative stress deteriorated. Negative correlations were found between MMA%, PMI and GSH, SOD, and TAOC, while DMA% and SMI positively correlated with the levels of ALT and AST. PMI and SMI negatively correlated with TAOC, GSH, SOD, ALT, and AST, positively linked with the level of MDA. The present study demonstrates that the hepatotoxicity induced by the arsenic accounts for deteriorating oxidative injury activized by arsenic methylation metabolism, providing additional evidence to suggest a mechanism of arsenic poisoning. Therefore, reducing the process of arsenic methylation may be potentially benefical in treating and – more importantly – preventing arseniasis.