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1

System dynamics research on economic transformation and environmentally coordinated development in China’s Eastern Coastal Region

100%
Li T., Liu N., Zhang Q.
Polish Journal of Environmental Studies
|
2019
|
tom 28
|
nr 5
The developed eastern coastal cities of China are leaders of the national economy, which is growing rapidly. However, with this growth has come substantial misuse of resources causing significant environmental damage, including some 85% of global greenhouse gases resulting from the impact of economic development. To explore a reasonable approach to coordinated development of economic growth and the environment, this paper assesses the city of Qingdao, employing regression analysis and other methods to establish an economic-energy-carbon emissions-social system dynamics model with a new industrial structure based on the degree of pollution. On the basis of new industrial structures, three separate schemes are formed by different combinations of sensitive variables. The research shows that over-emphasis on the environment or production of control measures are not appropriate under the current economic modality. Overemphasis on the environment will lead to rapid decline in economic growth and even the loss of economic growth momentum. Over-emphasis on production will result in a sharp increase in carbon emissions, accelerating the destruction of the environment and causing irreparable losses. Only by taking moderate measures on the basis of the current economic conditions can we achieve the desired economic and ecological goals.
2

Structural diversity closely associated with canopy species diversity and stand age in species-poor montane forests on Loess Plateau of China

100%
Liu N., Wang H., Nan H.
Polish Journal of Ecology
|
2017
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tom 65
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nr 2
High species diversity is often accompanied with and supported by a diversified stand structure in species-rich natural forests. However, the relationship between species diversity and stand structural diversity is less examined in species-poor forests. In montane forests on Loess Plateau of north-central China in a semi-arid climate zone, canopy species diversity and vertical structure of 57 broadleaves, conifer and mixed stands, with varying stand ages and site conditions, were randomly sampled. Canopy species diversity was represented by Shannon's index (H'). Stand structural diversity was represented by two indices respectively, i.e. coefficients of variation of diameter measurements at breast height (CVdbh) and Shannon's index of diameter classes (H'dbh). Structural equation models (SEMs) were constructed to explore multiple relationships between stand structural diversity and canopy species diversity, stand age and elevation. Both stand structural diversity indices increased directly with H' and stand age. However, indirect positive effect of stand age via increasing H' was only significant on CV. H'dbh provided positive feedback on H', while effect of stand age was only indirect via increasing structural diversity. Elevation significantly affected coefficients of variation of diameter, which was probably a sampling effect due to narrow distribution of broadleaves-conifer stands in altitudinal range. In conclusion, the results showed that stand structural diversity and canopy species diversity and stand age are closely associated with the species-poor montane forests like these on Loess Plateau of north-central China.
3
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Optimal design of a furniture frame by reducing the volume of wood

100%
Hu W., Liu N., Guan H.
Drewno. Prace Naukowe. Doniesienia. Komunikaty
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2019
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tom 62
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nr 204
4

Factors altering the membrane fluidity of spinach thylakoid as determined by fluorescence polarization

100%
Lin Z. F., Liu N., Lin G. Z., Peng C. L.
Acta Physiologiae Plantarum
|
2011
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tom 33
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nr 3
Alterations in fluidity of thylakoid membranes isolated from spinach chloroplasts in response to sodium bisulfite (NaHSO₃), hydrogen peroxide (H₂O₂), sodium dodecyl sulfate (SDS), bovine serum albumin (BSA), and free linoleic acid (LA) were investigated by means of a fluorescence polarization study with 1,6-diphenyl-1,3,5- hexatriene as the fluorescence probe. A decrease in fluidity and an increase in microviscosity of membrane were caused by NaHSO₃ and H₂O₂ treatment. In contrast, SDS and BSA were found to increase thylakoid membranes fluidity and decrease microviscosity, in which the corresponding correlation coefficients were -0.9995 to -0.9516 (SDS) and -0.9359 (BSA), respectively. No changes in thylakoid membranes fluidity induced by free LA were found until its concentration above 5 mM where the polarization value (P value) declined (increased fluidity). The results suggest that the changes in thylakoids membrane fluidity might depend on the characteristics, mechanism and extent of the interactions between membrane components and compounds added.
5

Effect of complexation conditions on microcapsulation of Lactobacillus acidophilus in xanthan-chitosan polyelectrolyte complex gels

76%
Chen H., Song Y., Liu N., Wan H., Shu G., Liao N.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2015
|
tom 14
|
nr 3
Background. Lactobacillus acidophilus has become increasingly popular because of their beneficial effects on health of their host, and are called proboscis. In order to exert beneficial effects for probiotics, they must be able to tolerate the acidic conditions of the stomach environment and the bile in the small intestine. Micro- encapsulated form has received reasonable attention, since it can protect probiotic organisms against an unfavourable environment, and to allow their release in a viable and metabolically active state in the intestine. The aim of this study was to investigate some factores, such as chitosan solution pH and concentration, xanthan concentration, cell suspension-xanthan ratio, mixed bacteria glue liquid-chitosan ratio, which impacted the process of microencapsulation of L. acidophilus. Material and methods. In this study, L. acidophilus was immobilized with xanthanthitosan gel using extrusion method. The viable counts and encapsulation yield of L. acidophilus encapsulated in different chitosan solution pH (4.5, 5, 5.5 and 6), in different chitosan concentration (0.5%, 0.7%, 0.9% and 1.1%), in different xanthan concentration (0.5%, 0.7%, 0.9% and 1.1%), in different cell suspension-xanthan ratios (1:5, 1:10, 1:15 and 1:20), in different mixed bacteria glue liquid-chitosan ratios (1:3,1:4,1:5 and 1:6), have been investigated by single factor experiment method. Results. The optimum conditions of microencapsulated L. acidophilus have been observed. The optimum chitosan solution pH for L. acidophilus was 5.5; the optimum chitosan concentration was 0.9%; the optimum xanthan concentration was 0.7%; the optimum cell suspension-xanthan ratio was 1:10; the optimum mixed bacteria glue liquid-chitosan ratio was 1:3. Conclusions. These results will be helpful to further optimize the process of L. acidophilus microencapsulation, and provide reference for obtaining higher viable counts and entrapped yield of L. acidophilus microcapsules.
6

A comparative assessment on soil environment quality based on chemical analyses of heavy metals

76%
Liu N., Tian F., Yang L., Li W., Fan H., Xia J.
Polish Journal of Environmental Studies
|
2015
|
tom 24
|
nr 5
This study investigated the concentrations of 11 metals in soils sampled in 1994 and 2014 from 17 cities throughout Anhui Province in China. Among the tested metals, Mn had the highest concentration and Hg the lowest. In the past 20 years, soil Cd, Co, Mn, and Cu concentrations demonstrated an increasing trend. In 1994, only Tongling City had a total metal concentration over 1,000 mg/kg, but in 2014, the seriously polluted cities also included Bengbu, Chizhou, Fuyang, Huannai, Huangshan, and Maanshan. Four assessment methods (two pollution indexes and two fuzzy mathematical models) were employed to investigate the soil environment quality of 17 cities. Environmental quality was determined to be Class I (excellent) or Class II (good) for each soil with single-factor index method, and most was identified as Class I for soils with the comprehensive index model. Different from the single-factor index method, the comprehensive index model concerned both the predominant index and average contribution of all pollution indices to integrated environmental quality. Using each of the two fuzzy mathematical methods (single-factor deciding and weighted average models), the environmental risks were determined to be Class I. However, divergence of the membership degree to each pollution class still occurred between the two methods. For fuzzy mathematical methods, membership functions were used to describe the limits between different pollution degrees, and different weights were allocated for the factors according to pollution contribution. Introduction of membership degree and weight of each factor to fuzzy mathematical models made the methods more reasonable in the field of environmental risk assessment.
7

Effects of feeding naturally contaminated diet with zearalenone, fumonisin and deoxynivalenol with or without yeast cell wall adsorbent on growth, vulva size and organ weights of gilts

64%
Liu N., Yang L., Yang W. R., Jiang S. Z., Zhang G. G., Niu Q. S., Qian X., Yang Z. B.
Journal of Animal and Feed Sciences
|
2016
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tom 25
|
nr 2
The aim of the study was to evaluate the effects of feeding naturally contaminated diet with Fusarium mycotoxins with or without yeast cell wall (YCW) on growth, vulva size, serum protein chemistry and organ weights of gilts. Forty gilts (8.33 ± 0.96 kg) were fed for 30 days four different diets: 1. control, 2. naturally contaminated diet (NCD), 3. naturally contaminated diet + 0.10% YCW, 4. naturally contaminated diet + 0.25% YCW. After 30 days of feeding with NCD diet average daily gain (ADG), feed conversion ratio, final body weight, serum albumin concentration and relative weight of liver were reduced (P < 0.05) in comparison to control group. In contrast, vulva size and relative weight of genital organs were increased (P < 0.05) by mycotoxins. The 0.25% YCW addition diminished the NCD negative effect on ADG, albumin concentration, and liver and genital organs weights throughout 30 days (P < 0.05). The lower YCW addition reversed only the negative effect of mycotoxins on liver weight. The vulva length was decreased by higher YCW dose but only at day 12. The addition of YCW could not ameliorate the enlarged vulva width and vulva area caused by mycotoxins. Based on the obtained results, it was showed that Fusarium mycotoxins lead to pernicious effects for gilts, but YCW addition to the diet can to some extent effectively ameliorate these detrimental mycotoxins effects.
8

Non-carcinogenic risks induced by heavy metals in water from a Chinese river

64%
Liu N., Zhu Q.-Y., Qian X., Yang L., Dai M.-Z., Jiang X.-Q., Li N., Sun L., Liu Z.-C., Lu G.-F.
Polish Journal of Environmental Studies
|
2012
|
tom 21
|
nr 4
Our study assessed the non-carcinogenic risks of heavy metals in the sources of drinking water treatment plants located along Huaihe River in Jiangsu Province, China. High-resolution inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectroscopy were used to determine the levels of eight metals in the water from 30 treatment plants. Non-carcinogenic risks induced by the metals were assessed using the methods recommended by the Environmental Protection Agency of the United States. Among the metals, Fe had the highest concentration and Pb contributed most to the average hazard index (HI) of 30 TWTPs. Except Pb, each metal had an average concentration below the permissible limit of China and the United States. The induced non-carcinogenic risks showed temporal and spatial variations. This study revealed that the metals in the tap water induced negligible public health risks for local residents.
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