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1

Flocculation/dispersion of hematite with caustic digested starch

100%

Tang M. , Wen S.

Physicochemical Problems of Mineral Processing

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2015

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tom Vol. 51, iss. 2

477--489

EN

Selective flocculation of hematite with starch is a process well-known in practice. However, the separation of hematite from other minerals depends strongly on the methods of starch digestion performed either as heating-digestion or alkali-digestion (different type and dosage of alkali). The purpose of this study is to identify possible influence of the alkali-digested starch on flocculation of ultra-fine hematite when the starch was digested at different concentrations of sodium hydroxide at room temperature. Adsorption of starch digested with sodium hydroxide at different concentration on hematite was investigated by abstraction and co-precipitation tests. Turbidities tests, settling rates, flocculation/dispersion measurement and Fourier transform infrared spectroscopic analysis (FTIR) have also been conducted. Based on the results of the above mentioned tests it is suggested that the flocculating power of caustic digested starch towards fine particles may be significantly weakened, while its dispersing ability starts to play a role instead, if the concentration of sodium hydroxide is high enough in starch digestion. When the weight ratio of NaOH /starch is lower than 2, incomplete gelatinization of starch granules may lead to coagulation of fine particles of hematite mostly due to non-selective electrostatic attraction. The weight ratio of NaOH /starch from 2 to 4 helps to flocculate mineral surfaces selectively and efficiently, assuring a complete digestion of starch granules and a small amount of acidic functional products on the starch chain. However, much smaller and homogenous short-chain granules resulting from higher concentration of sodium hydroxide (the weight ratio of NaOH /starch is more than 4) used to digest starch may weaken the flocculating capacity of the caustized starch for hematite and lead to its dispersion.

2

High genetic diversity in the naturally rare plant Taihangia rupestris Yu et Li (Rosaceae) dwelling only cliff faces

80%

Tang M. , Yu F. , Jin X. , Ge S.

Polish Journal of Ecology

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2010

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tom Vol. 58, nr 2

241-248

EN

Cliffs are the primary habitat of many rare and endangered plant species, but few studies have investigated the genetic diversity of these species. Taihangia rupestris Yu et Li (Rosaceae) is the only species of the genus Taihangia, which occurs exclusively in small crevices on the faces of north-facing vertical cliffs at altitudes ranging from 600 to 1500 m above sea level. It is a perennial herb endemic to the southern part of the Taihang Mountains in northern China. We sampled fresh leaves from 11 to 38 individuals of T. rupestris in each of eight cliff-face populations located in the provinces of Hebei, Shanxi and Henan in China. The leaves were dried by silica gel and DNA was extracted. We then assessed the genetic variability within and among the eight populations of T. rupestris using random amplified polymorphic DNA (RAPD). Within the 150 plants sampled, 81.2% of the 117 RAPD markers detected were polymorphic, and Nei.s diversity (H) was on average 0.21 in the eight populations and 0.28 in the species as a whole. The grouping of the eight populations by clustering analysis agreed with their pattern of geographical distribution and with the separation of the species into two varieties (T. rupestris var. ciliata and T. rupestris var. rupestris). Genetic distances ([Phi]st) were significantly correlated with geographic distances. Although significant genetic differentiation existed between groups (varieties) and among populations, a high proportion (65.4%) of the total genetic variation was maintained within populations. Therefore, high genetic diversity is preserved in the cliffdwelling populations, and in situ protection of T. rupestris should focus on the protection of the habitat of both varieties, which may be of particular importance for the long-term survival of this species.

3

Loureirin B inhibits the proliferation of hepatic stellate cells and the Wnt/β-catenin signaling pathway by regulating miR-148-3p

80%

Hu J. , Zhang R. , Tang M. , Li Y.

Cellular and Molecular Biology Letters

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2018

|

tom 23

EN

Background: We investigated the activity of loureirin B against liver fibrosis and the underlying molecular mechanisms. Methods: Hepatic stellate cells (HSCs) from Sprague-Dawley rats were treated with different concentrations of loureirin B. We used the MTT assay to determine HSC proliferation, flow cytometry to analyze apoptosis, and western blot to determine the expressions of Bax, Bcl-2, Wnt1 and β-catenin. Real-time PCR was used to determine the expressions of Wnt1 and miR-148-3p. Results: The MTT assay showed that loureirin B treatment significantly inhibited the proliferation of HSCs in time- and dose-dependent manners. Loureirin B significantly promoted the apoptosis of HSCs, increased the expression of Bax and decreased the Bcl-2 level. Western blot analysis showed that the expressions of Wnt1 and β-catenin were obviously lower in the loureirin B treatment group than in the control group. We also found that loureirin B could decrease the Wnt1 mRNA level and increase miR-148-3p expression. Knockdown of miR-148-3p using inhibitor could reverse the effects of loureirin B on the proliferation and apoptosis of HSCs and the expressions of Bax, Bcl-2, Wnt1 and β-catenin. Conclusion: Our results suggest that loureirin B inhibited the proliferation and promoted the apoptosis of HSCs, and suppressed the Wnt/β-catenin signaling pathway via regulation of miR-148-3p.

4

High genetic diversity in the naturally rare plant Taihangia rupestris Yu et Li (Rosaceae) dwelling only cliff faces

80%

Tang M. , Yu F.-H. , Jin X.-B. , Ge S.

Polish Journal of Ecology

|

2010

|

tom 58

|

nr 2

EN

Cliffs are the primary habitat of many rare and endangered plant species, but few studies have investigated the genetic diversity of these species. Taihangia rupestris Yu et Li (Rosaceae) is the only species of the genus Taihangia, which occurs exclusively in small crevices on the faces of north-facing vertical cliffs at altitudes ranging from 600 to 1500 m above sea level. It is a perennial herb endemic to the southern part of the Taihang Mountains in northern China. We sampled fresh leaves from 11 to 38 individuals of T. rupestris in each of eight cliff-face populations located in the provinces of Hebei, Shanxi and Henan in China. The leaves were dried by silica gel and DNA was extracted. We then assessed the genetic variability within and among the eight populations of T. rupestris using random amplified polymorphic DNA (RAPD). Within the 150 plants sampled, 81.2% of the 117 RAPD markers detected were polymorphic, and Nei’s diversity (H) was on average 0.21 in the eight populations and 0.28 in the species as a whole. The grouping of the eight populations by clustering analysis agreed with their pattern of geographical distribution and with the separation of the species into two varieties (T. rupestris var. ciliata and T. rupestris var. rupestris). Genetic distances (Φst) were significantly correlated with geographic distances. Although significant genetic differentiation existed between groups (varieties) and among populations, a high proportion (65.4%) of the total genetic variation was maintained within populations. Therefore, high genetic diversity is preserved in the cliffdwelling populations, and in situ protection of T. rupestris should focus on the protection of the habitat of both varieties, which may be of particular importance for the long-term survival of this species.

5

Influence of arbuscular mycorrhiza on photosynthesis and water status of Populus cathayana Rehder males and females under salt stress

80%

Wu N. , Li Z. , Liu H. , Tang M.

Acta Physiologiae Plantarum

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2015

|

tom 37

|

nr 09

EN

The influence of arbuscular mycorrhizal fungi (AMF) Rhizophagus irregularis on biomass, root morphological characteristics, water status, gas exchange and ion contents of Populus cathayana Rehder males and females under salt stress was studied in a greenhouse experiment. Sex had no influence on AMF colonization. Salt stress decreased the biomass, modified root characteristics, inhibited photosynthesis, relative water content (RWC), while increased the water use efficiency (WUEi), the ratio of root/shoot (RSR) and salt ion contents within the plants. Males and females differed in response to the salt stress and AMF inoculation. AMF inoculation increased the biomass of root, the biomass of shoot, and decreased RSR, especially in males. The root length, root volume (RV), root surface area, and root tip numbers (RTN) were increased with AMF inoculation in males, while RV and RTN were decreased with AMF inoculation in females. AMF had positive effects on RWC and WUEi in both sexes. Mycorrhizal cuttings also had higher gas exchange capacity, lower salt ion contents than non-mycorrhizal cuttings. The principal component analysis showed that males exhibited a better salt tolerance than females, and AMF inoculation had positive effects on both sexes, especially in males.

6

Nutrient allocation and photochemical responses of Populus × canadensis ‘Neva’ to nitrogen fertilization and exogenous Rhizophagus irregularis inoculation

80%

Wu F. , Zhang H. , Fang F. , Tang M.

Acta Physiologiae Plantarum

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2018

|

tom 40

|

nr 08

7

Hybrid fault diagnosis of railway switches based on the segmentation of monitoring curves

80%

Ou D. , Tang M. , Xue R. , Yao H.

Eksploatacja i Niezawodność

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2018

|

tom Vol. 20, no. 4

514--522

EN

Switches are one of the most important pieces of infrastructure in railway signal systems, and they significantly influence the efficiency and safety of train operation. Currently, the identification of switch failures mainly depends on the experience of railway staff and the use of simple thresholding methods. However, these basic methods are highly inaccurate and frequently result in false and missing alarms. This paper aims to develop a hybrid fault diagnosis (HFD) method for railway switches. The method is an intelligent diagnosis method that uses massive current curves collected by microcomputer monitoring systems. We first divide the switch operation current curves into three segments based on the three mechanical processes that occur during switch operation. Then, a standard curve is selected from the fault-free curves, and common typical faults are ascertained through a microcomputer monitoring system. Finally, derivative dynamic time warping and a quartile scheme are employed to identify fault curves. An experiment based on current curves collected from the Guangzhou Railway Bureau in China demonstrates that the HFD method is extremely accurate and has low false and missing alarm rates. HFD performs better than the studied support vector machine (SVM) and dynamic time warping (DTW) methods, which are widely used for fault diagnosis.

PL

Zwrotnice stanowią jeden z najważniejszych elementów infrastruktury systemów sygnalizacji kolejowej i mają znaczący wpływ na wydajność i bezpieczeństwo eksploatacji pociągów. Obecnie, identyfikacja awarii zwrotnic zależy głównie od doświadczenia personelu kolejowego i opiera się na stosowaniu prostych metod progowania. Jednakże te elementarne metody są wysoce niedokładne i często skutkują fałszywymi alarmami lub brakiem alarmu. Niniejszy artykuł ma na celu opracowanie hybrydowej metody diagnostyki błędów (HFD) dla zwrotnic kolejowych. Metoda ta jest inteligentną metodą diagnostyczną, która wykorzystuje wykresy przebiegu prądowego zebrane przez mikrokomputerowe systemy monitorowania. Najpierw krzywe prądowe działania zwrotnicy dzieli się na trzy segmenty w oparciu o trzy procesy mechaniczne, które zachodzą podczas jej działania. Następnie, spośród krzywych opisujących działanie bezusterkowe, wybiera się przebieg standardowy, a w dalszej kolejności ustala się, z wykorzystaniem mikrokomputerowego systemu monitorowania, najczęściej występujące, typowe błędy działania zwrotnicy. Wreszcie, do identyfikacji krzywych błędów stosuje się schemat kwartylowy oraz metodę derivative dynamic time warping wykorzystującą pochodne do klasyfikacji szeregów czasowych. Eksperyment oparty na krzywych prądowych zebranych przez Guangzhou Railway Bureau w Chinach pokazuje, że metoda HFD jest wyjątkowo dokładna i skutkuje niską liczbą fałszywych i brakujących alarmów. HFD daje lepsze wyniki niż szeroko stosowane do diagnozowania błędów metody maszyny wektorów nośnych (SVM) i dynamic time warping (DTW).

8

Caustic-digested starch and its adsorption on hematite

80%

Tang M. , Wen S. , Tong X.

Physicochemical Problems of Mineral Processing

|

2017

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tom Vol. 53, iss. 1

69--81

EN

Adsorption characteristics on hematite of caustic-digested starch by sodium hydroxide or potassium hydroxide were investigated through a series of tests, like adsorption tests, paste titration and zeta potentials measurement, scanning electron microscope measurement (SEM) and Fourier transform infrared spectroscopic analysis (FTIR) as well. An attempt was made in order to identify the possible effects of starch digested with alkali at different concentrations on its adsorption on mineral surfaces. All results pointed out that a different amount of carboxyl groups in the starch gel were harvested from alkali-digestion as a function of concentrations of sodium hydroxide or potassium hydroxide; more acidic groups were produced if higher concentrations of alkali were added. These carboxyl groups may contribute the acid/base interaction of the caustic-digested starch on hematite. Also, different concentrations of sodium hydroxide to digest starch seem to induce different degrees of its gelatinization from the SEM results, partially attributing to a wide range of its adsorption capacities on mineral surfaces. The optimum adsorption density of the caustic-digested starch on mineral surfaces, 9.87 mg/g hematite for sodium hydroxide and 10.51 mg/g hematite for potassium hydroxide, respectively, was achieved at the weight ratio of starch to sodium/potassium hydroxide as 1:2.

9

Analysis of the start-up of natural bio-film colonization of constructed rapid infiltration system

70%

Xu W. , Yang J. , Wang J. , Jian Y. , Tang M.

Polish Maritime Research

|

2016

|

tom 23

|

nr Special Issue S1

EN

Abstract: this paper studied the start-up of natural bio-film colonization under the conditions where wet-to-dry ratio was 1:6, hydraulic load was 0.8m3/m2·d, and water temperature was 100C-150C, it took 25d in total to become mature, after the success of bio-film colonization, the removal rate of COD and NH4+-N can be stabilized at 80%, and the removal rate of NH4+-N can reach 90% above. The microorganism was divided into the following stages during bio-film colonization:1. Reversible adhesion of cell on the surface of the carrier, 2.Irreversible adhesion of cell on the surface of the carrier, 3.Division of cell adhering to the surface of the carrier and formation of microcolony adhering to the surface of the carrier, 4.Growth of microcolony adhering to the surface of the carrier to be mature bio-film with three-dimensional structure. The process of natural bio-film colonization can be judged comprehensively according to removal rate of NH4+-N and COD, effluent pH as well as color of microbial film

10

Analysis of the start-up of natural bio-film colonization of constructed rapid infiltration system

70%

Xu W. , Yang J. , Wang J. , Jian Y. , Tang M.

Polish Maritime Research

|

2016

|

tom S 1

32--35

EN

Abstract: this paper studied the start-up of natural bio-film colonization under the conditions where wet-to-dry ratio was 1:6, hydraulic load was 0.8m3/m2·d, and water temperature was 100C-150C, it took 25d in total to become mature, after the success of bio-film colonization, the removal rate of COD and NH4+-N can be stabilized at 80%, and the removal rate of NH4+-N can reach 90% above. The microorganism was divided into the following stages during bio-film colonization:1. Reversible adhesion of cell on the surface of the carrier, 2.Irreversible adhesion of cell on the surface of the carrier, 3.Division of cell adhering to the surface of the carrier and formation of microcolony adhering to the surface of the carrier, 4.Growth of microcolony adhering to the surface of the carrier to be mature bio-film with three-dimensional structure. The process of natural bio-film colonization can be judged comprehensively according to removal rate of NH4+-N and COD, effluent pH as well as color of microbial film.

11

Can China achieve its CO2 emission mitigation target in 2030: a system dynamics perspective

70%

Zhang L. , Jiang Z. , Liu R. , Tang M. , Wu F.

Polish Journal of Environmental Studies

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2018

|

tom 27

|

nr 6

EN

To predict the feasibility of whether China can achieve an up to 65% of carbon emissions intensity (CEI) reduction goal from 2005 levels by 2030, we performed dynamic simulations and predictions of China’s CO₂ emissions at the national scale from a system dynamics perspective. More specifically, we developed a system dynamics model based on LMDI analysis to simulate and estimate CO₂ emissions under 10 different scenarios in China during 1991-2030. The result shows that China’s CEI will decrease by 67.86-84.63% in 2030 compared to the 2005 level, which means that China will be able to meet the emission reduction goal by 2030, and China’s CO₂ emissions will peak sometime between 2020 and 2025. In addition, the quantitative evidence suggests that transforming the energy structure will make a significant contribution to CO₂ emissions reduction. As the proportion of renewables increases, CO₂ emissions decrease in terms of both scale and peak value and peaks earlier. So, the findings also indicate that the optimization for energy structure by replacing fossil fuels (especially coal) with renewables at a suitable growth rate can promote the coordination between economic growth and CO₂ emissions mitigation.

12

Effect of Rhizophagus irregularis on osmotic adjustment, antioxidation and aquaporin PIP genes expression of Populus x canadensis ‘Neva’ under drought stress

70%

Liu T. , Li Z. , Hui C. , Tang M. , Zhang H.

Acta Physiologiae Plantarum

|

2016

|

tom 38

|

nr 08

13

Effects of arbuscular mycorrhizal colonization on the biomass and bioenergy production of Populus x canadensis "Neva" in sterilized and unsterilized soil

61%

Liu T. , Wang C. , Chen H. , Fang F. , Zhu X. , Tang M.

Acta Physiologiae Plantarum

|

2014

|

tom 36

|

nr 04

EN

Arbuscular mycorrhizal (AM) symbiosis can improve the growth of poplar, which is considered to be a bioenergy feedstock and a substitute for fossil fuels. Microbes in plant rhizosphere may affect the interaction between AM fungi and host plant. The role of AM fungi on the biomass and bioenergy production of poplar in the presence or absence of other soil microorganisms was less investigated. In this study, the effects of Rhizophagus irregularis and Glomus versiforme on the growth, root-absorbing area, chlorophyll content, gas exchange, total organic carbon (TOC) content, gross calorie value (GCV), lignin and cellulose content of Populus × canadensis ‘Neva’ in sterilized and unsterilized soil were evaluated. The results showed that AM symbiosis increased the biomass parameters such as stem length, ground diameter, dry weight, root-absorbing area, chlorophyll content and gas exchange capacity, as well as bioenergy parameters such as TOC content, GCV and lignin content of poplar seedlings, but did not affect the cellulose content. The extent of this enhancement varied within AM fungi species and soil conditions. The effect of AM was higher in sterilized soil than that in unsterilized soil, and the function of R. irregularis was greater than G. versiforme in sterilized soil, but lower in unsterilized soil. In general, G. versiforme exhibited higher applying potential in the biomass and bioenergy production of poplar.