Wyniki wyszukiwania - Biblioteka Nauki

1

A new method of line feature generalization based on shape characteristic analysis

100%

Huang Z. , Nie H.

|

tom Vol. 18, nr 4

597-605

EN

This paper presents a piecewise line generalization algorithm (PG) based on shape characteristic analysis. An adaptive threshold algorithm is used to detect all corners, from which key points are selected. The line is divided into some segments by the key points and generalized piecewise with the Li-Openshaw algorithm. To analyze the performance, line features with different complexity are used. The experimental results compared with the DP algorithm and the Li-Openshaw algorithm show that the PG has better performance in keeping the shape characteristic with higher position accuracy.

2

Optimization and performance of moderate combined alkali and microwave pretreatment for anaerobic digestion of waste-activated sludge

70%

Jiang H. , Liu T. , Ding J. , Nie H. , Jiang H.

Polish Journal of Environmental Studies

|

2018

|

tom 27

|

nr 2

EN

For pretreating waste-activated sludge, the combined alkali and microwave pretreatment is a promising hybrid method. To make this pretreatment more economical, moderate conditions were applied for central composite design of the experiments. A quadratic model was established to describe the influence of NaOH dosage and microwave processing time on methane production. The optimal condition was 0.12 g NaOH/g TS treatment for 24 h and 240 W microwave treatment for 10 min. Either single or hybrid pretreatment can significantly accelerate the hydrolysis, but the degree of degradation increases positively as correlated with treatment intensity. Comparing to untreated sludge, the methane yields of microwave-, alkali-, and combined-treated increased to 1.9, 3.4, and 4.6 times, respectively. The SCOD removal rates of the three kinds of treated sludge were 20.6%, 23.0%, and 36.5%, respectively. The single microwave pretreatment efficiently broke the sludge flocs and promoted the release of biodegradable organics as well as nutrients, but there was no advantage in methane production. The existence of NaOH not only eliminated the inhibition caused by microwave, but also improved the degree of degradation.

3

Influence of composition on the structure and properties of SrO-Sb2O3-P2O5 low-melting sealing glasses

61%

Nie H. , Zhang J. , Qi Y. , Wang Z. , Lin H. , Jiang S.

Materials Science Poland

|

2015

|

tom Vol. 33, No. 4

862--866

EN

SrO-Sb2O3-P2O5 glass system was prepared by high temperature melting method. The effects of Sb2O3 and P2O5 content on the structure, thermal behavior and chemical durability of the glasses were studied by infrared spectrometer, thermal dilatometer, differential thermal analyzer and constant temperature water bath heating. It can be concluded that the characteristic temperatures of the glasses increased firstly and then decreased with the increasing of Sb2O3 content, whereas the tendency of the coefficient of thermal expansion (CTE) varied inversely. The crystallization ability of the glasses was significantly increased and the water resistance was reduced for Sb2O3 content of 35 mol % and 40 mol %. The glasses with 20 mol %, 25 mol % and 30 mol % Sb2O3 showed better performance in every respect than the others and the glasses containing 25 mol % Sb2O3, characterized by the best performance, can be chosen as host glasses for further research.

4

Effects of recent and potential land use and climate changes on runoff and sediment load in the Upper Yellow River Basin, China

61%

Lv Z. , Qin T. , Wang Y. , Mu J. , Liu S. , Nie H.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 6

5

Initial start-up characteristics of anaerobic ammonium oxidation in a UASB reactor

61%

Cheng H. , Yan Y. , Yi X. , Wang J. , Xu W. , Nie H.

Polish Journal of Environmental Studies

|

2020

|

tom 29

|

nr 3

6

NaOH pretreatment of wheat straw at a mesophilic temperature: Effect on hydrolysis and loss of organic carbon

61%

Jiang H. , Zeng Y. , Nie H. , Li Y. , Ding J. , Zhou H.

Polish Journal of Environmental Studies

|

2016

|

tom 25

|

nr 4

EN

A common approach to increasing biogas production is enhancing the hydrolysis of wheat straw by removing the lignin-using chemicals. However, partial organic matter will also dissolve into chemical solutions during pretreatment, which leads to the loss of organic matter for the anaerobic digestion process. The enzymatic hydrolysis of wheat straw and loss of total organic carbon increased with NaOH concentration and pretreatment time. The results suggest that when evaluating a pretreatment method, not just the hydrolysis but the loss of organic matter should be taken into consideration.

7

Characteristics of kitchen waste and the formation of floating brown particles (FBP) in the anaerobic digestion process

51%

Li Y. , Jiang H. , Liu H. , Luo S. , Nie H. , Wang Y. , Qian M. , Ding J. , Zhou H.

Polish Journal of Environmental Studies

|

2018

|

tom 27

|

nr 1

EN

Five types of kitchen waste (KW) from China – including hop pot (HP), fast food (FF), Hebei cuisine (HC), university canteen (UC), and other mixed KW (Other) – were investigated as feedstock for potential biogas and methane production. The biodegradability of KW was measured using batch anaerobic digestion (AD) tests and feedstock at an inoculum ratio (F/I) of 0.5. Gompertz and Cone models were used to determine the kinetic parameters of KW degradation, biogas, and methane production. Results showed that HP had the highest lag phase time of 5.46 days. Methane production varies with different sources of KW. HP had the highest methane yield of 363.9 mL/g-VSadded as compared to a sample of FF (334.8 mL/g-VSadded), other ( 278.5 mL/g-VSadded), UC (239.2 mL/g-VSadded), and HC (236.0 mL/g-VSadded). The biodegradability of KW ranged from 39.5% to 50.4%. During the AD process a certain amount of floating brown particles (FBP) were formed, which may be the main inhibiting factor of methane production. Analysis of ¹³C NMR and FTIR revealed that the main component of FBP was calcium stearate. The formation mechanism of calcium stearate may contribute to the relatively high lipid content (18.6% to 30.9%) of the KW sample, which subsequently resulted in over-accumulation of long-chain fatty acids (LCFAs) and reaction with Ca²⁺. Using lipid-rich substrates as feedstock may be an efficient approach to adding Ca²⁺ artificially for reducing the inhibition of LCFAs.

8

Influence of organic loading rate on the performance of a two-phase pressurized biofilm (TPPB) system treating food waste

51%

Li Y. , Yan F. , Liu H. , Wang Y. , Nie H. , Jiang H. , Qian M. , Zhou H.

|

tom 26

|

nr 5

EN

A two-phase pressurized biofilm (TPPB) system, including a continuously stirred tank reactor (CSTR) and a pressurized biofilm anaerobic reactor (PBAR), was used to produce high calorific biogas without additional upgrading equipment. The influence of organic loading rate (OLR) on biogas and methane production performance was investigated. Three different OLR levels (4, 5, and 6 g-COD/L/d) were applied to the PBAR in sequence. The headspace pressure of PBAR was controlled at 1.0 MPa. Biogas production, gas composition, and process stability parameters were measured. Results found that the highest methane yield of 332.8 mL/g-COD was obtained at OLR of 5 g-COD/L/d. As compared to approximately 90% methane concentration at OLR of 3.1 g-COD/L/d, the methane content in produced biogas was only 76% at OLR of 5.0 g-COD/L/d. The pH value in the pressurized reactor has an important impact on the quality of produced biogas. Further study should focus on the solution strategies of maintaining suitable pH under higher pressure and higher OLR.