Wyniki wyszukiwania - Biblioteka Nauki

1

100%

Ferdows M. , Liu D.

International Journal of Applied Mechanics and Engineering

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2017

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tom Vol. 22, no. 1

253--258

EN

The aim of this work is to study the mixed convection boundary layer flow from a horizontal surface embedded in a porous medium with exponential decaying internal heat generation (IHG). Boundary layer equations are reduced to two ordinary differential equations for the dimensionless stream function and temperature with two parameters: ε, the mixed convection parameter, and λ, the exponent of x. This problem is numerically solved with a system of parameters using built-in codes in Maple. The influences of these parameters on velocity and temperature profiles, and the Nusselt number, are thoroughly compared and discussed.

2

Quantitative determination of glycerol in antarctic krill (Euphausia superba Dana) by high-performance thin-layer chromatography

100%

Han X. , Liu D.

Acta Chromatographica

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2018

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tom Vol. 30, no. 4

274--277

EN

In this reported study, a direct high-performance thin-layer chromatographic (HPTLC) method was developed to qualitatively detect and quantitatively determine glycerol in Antarctic krill for the first time. This procedure was based on the extraction of glycerol by ultrasonic solvent extraction with anhydrous ethanol, silica-gel column chromatographic separation, HPTLC detection and quantification using methylene chloride–methanol (5:1, v/v) as the developing solvent and alkaline potassium permanganate as chromogenic agent. The content of glycerol was 1.3725 ± 0.218 mg/g in freeze-dried Antarctic krill. The structure of glycerol in the Antarctic krill was subsequently determined by gas chromatography–mass spectrometry (GC–MS) which verified the presence of the material in the krill. The HPTLC method exhibited excellent accuracy with a recovery of 90.1–103.3% and good precision with a relative standard deviation (RSD) of 1.59–4.84%. The results clearly exhibited the applicability of the proposed for quantifying glycerol in Antarctic krill.

3

Key Technologies of Information Exchange in Electric Utility Based on IEC 61968

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Lu Y. , Liu D.

Przegląd Elektrotechniczny

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2012

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tom R. 88, nr 11a

276-282

EN

The research on interoperability testing and implementation methodology of IEC 61968 has been carried out for many years. But there are still many problems to be solved. This paper proposes a practical architecture for information exchange based on IEC 61968 to bridge the gaps between theory and practice. Some novel and original implementation technologies are elaborated covering model, profile, metadata and verification aspects. Finally the feeder data integration case for local utility business demonstrates the feasibility and effectiveness of the proposed architecture.

PL

W artykule przedstawiono praktyczną budowę struktury wymiany informacji opartą na standardzie IEC 61968. Opisano nowatorskie sposoby implementacji modelu, profilu, meta danych oraz przykład wykorzystania, weryfikujący wykonalność i efektywność proponowanej struktury.

4

An Ontological Meta-Model Framework for Implementation of IEC 61968

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Lu Y. , Liu D.

Przegląd Elektrotechniczny

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2012

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tom R. 88, nr 11a

232-235

EN

The ontological meta-model abstract framework is the base for IEC 61968 implementation. The layered framework covers all aspects of process of information integration on utility level in smart grid. The ontology and methodology of model transformation, model modification, business context and integration pattern components are separately elaborated by using ontological meta-model. The formal method for the implementation algorism and verification tools is also presented.

PL

W artykule przedstawiono propozycję ontologicznej struktury meta-modelu i komponentów standardu IEC 61968. Struktura ma na celu ustalenie specyfikacji standardu na potrzeby późniejszych prac.

5

New species of oribatid mites of the families Parakalummidae and Galumnidae (Acari: Oribatida) from Xiao Hinggan Mountains, Northeastern China

100%

Liu D. , Wu D.

Annales Zoologici

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2013

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tom 63

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nr 2

EN

Two new species of oribatid mites, Sandenia (Porokalumma) elongata sp. nov. (Parakalummidae) and Pergalumna distincta sp. nov. (Galumnidae), are described and illustrated from Xiao Hinggan Mountains in Northeastern China.

6

Descriptions of two new species of Austrophthiracarus Balogh et Mahunka, a newly recorded genus of ptyctimous mites from China (Acari: Oribatida: Phthiracaridae)

100%

Liu D. , Chen J.

Annales Zoologici

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2014

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tom 64

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nr 2

EN

The oribatid mite genus Austrophthiracarus Balogh et Mahunka (Phthiracaridae) is recorded for the first time from China. Two new species of Austrophthiracarus are described: A. filiformis sp. nov. and A. longisetosus sp. nov. Their morphological descriptions and illustrations are given.

7

Dolegliwości kręgosłupa przyczyny i sposoby ochrony

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Kamińska J. , Liu D.

Bezpieczeństwo Pracy : nauka i praktyka

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2000

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tom nr 4

16-19

8

Taxonomic study of the genus Maerkelotritia Hammer, 1967 (Acari: Oribatida: Oribotritiidae) from China, with description of a new species

80%

Liu D. , Niedbala W. , Chen J.

Annales Zoologici

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2009

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tom 59

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nr 4

EN

The genus Maerkelotritia is reviewed. Maerkelotritia fusifomtis sp. nov. from litter in temperate forest in Shanxi Province, China, is described, and one newly recorded species, M. krivolutzkii Märkel, 1968, is redescribed. M. kirghizica Niedbała, 2006 is considered as a new junior synonym of M. krivolutzkii. The genus Maerkelotritia is reported for the first time from China.

9

Detonation Reaction Characteristics for CL-20 and CL-20-based Aluminized Mixed Explosives

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Liu D. , Chen L. , Wang C. , Wu J.

Central European Journal of Energetic Materials

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2017

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tom Vol. 14, no. 3

573--588

EN

The interfacial particle velocities for CL-20 and CL-20-based aluminized mixed explosives were measured by interferometry in order to analyze the aluminum reactions in the latter. The reaction characteristics were obtained, as well as a better understanding of the effects of aluminum powder on the detonation reaction zone length. Two functions were used to fit the particle velocity-time profiles, and their intersection was the corresponding Chapman-Jouget (CJ) point. From these profiles, the detonation reaction zone length and the aluminum reaction were then analyzed. CL-20-based explosives have a short reaction time (48 ns for a high CL-20 content), while the reaction time of CL-20/Al explosives increased with the aluminum content and particle size. Micron-scale aluminum particles barely reacted in the CL-20 detonation reaction zone, but instead reacted with the detonation products after the CJ point. This reduced the detonation pressure; however, the aluminum reaction can slow down the decrease in particle velocities. The start times of small-particle aluminum reactions were earlier than those of the larger particles. The 2-3-μm aluminum particles start to react within 1 μs after the CJ point, while the 200-nm particles may start to react in the reaction zone.

10

Effects of cadmium stress on root tip cells and some physiological indexes in Allium cepa var. agrogarum L.

80%

Zou J. , Yue J. , Jiang W. , Liu D.

Acta Biologica Cracoviensia. Series Botanica

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2012

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tom 54

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nr 1

EN

Allium cepa var. agrogarum L. seedlings grown in nutrient solution were subjected to increasing concentrations of Cd2+ (0, 1, 10, 100 μM). Variation in tolerance to cadmium toxicity was studied based on chromosome aberrations, nucleoli structure and reconstruction of root tip cells, Cd accumulation and mineral metabolism, lipid peroxidation, and changes in the antioxidative defense system (SOD, CAT, POD) in leaves and roots of the seedlings. Cd induced chromosome aberrations including C-mitoses, chromosome bridges, chromosome fragments and chromosome stickiness. Cd induced the production of some particles of argyrophilic proteins scattered in the nuclei and even extruded from the nucleoli into the cytoplasm after a high Cd concentration or prolonged Cd stress, and nucleolar reconstruction was inhibited. In Cd2+-treated Allium cepa var. agrogarum plants the metal was largely restricted to the roots; very little of it was transported to aerial parts. Adding Cd2+ to the nutrient solution affected mineral metabolism. For example, at 100 μM Cd it reduced the levels of Mn, Cu and Zn in roots, bulbs and leaves. Malondialdehyde content in roots and leaves increased with treatment time and increased concentration of Cd. Antioxidant enzymes appear to play a key role in resistance to Cd under stress conditions.

11

Nutrient resorption and use efficiency at different canopy heights of Alpine tree species Abies georgei var. smithii [Viguie et Gaussen] Cheng, Tibetan Plateau

80%

Li M. , Liu D. , Kong G.

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nr 1

63-72

EN

Nutrients may be mobilized from senescing leaves and transported to other plant tissues, enabling plants to conserve them and reuse. Nitrogen and phosphorus are two dominant nutrients related to photosynthetic capacity and limiting plant growth. In this study, we examined the effect of canopy height on nutrient use by analyzing N and P concentrations of green and senescent leaves collected from different canopy heights of Abies georgei var. smithii (Viguie et Gaussen) Cheng growing at the alpine timberline in Sergyemla Mt. (4 350 m a.s.l), southeastern Tibetan Plateau. The results showed that N and P concentrations per unit needle mass decreased significantly with needle age, but no significant difference was found among upper, middle and lower canopy. However, area-based N and P concentrations increased with the height of canopy. The leaf level nutrient resorption and use efficiency varied in the order: upper canopy> middle canopy >lower canopy for both N and P. The higher nutrient resorption efficiency had significant relationship with leaf level nutrient use efficiency, that is, higher leaf level nutrient use efficiency was partly due to the high resorption from senescent needles. Additionally, the higher nutrient resorption was related to high current nutrient concentration. Vertical variations of leaf level nutrient use efficiency in this study reflected the strategy of alpine trees to respond to imbalance between light availability and soil nutrients.

12

Research on High Quality Nanofiber Electrospinning Manufacturing System:Detecting Method of Taylor-cone and Fiber diameter Control Strategy

80%

Liu Y. , Jing C. , Liu D. , Hu Q.

Przegląd Elektrotechniczny

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2012

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tom R. 88, nr 9b

17-21

EN

This paper designed the method to control the electrospinning process stability basing on the analysis of Taylor-cone, and built the electric field adjust method to control the fiber diameter basing on the finite element analysis, experiments results showed that the stability was improved and diameter could the adjusted in micro-nano level.

PL

W artykule zaprezentowano metodę sterowania procesu produkcji nanowłókien bazująca na stożku Taylora i wykorzystaniu pola elektrycznego do kontroli średnicy włókna.

13

Metoda oceny pozycji przy pracy z wykorzystaniem rejestracji goniometrycznej

80%

Kamińska J. , Tokarski T. , Liu D.

Bezpieczeństwo Pracy : nauka i praktyka

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2000

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tom nr 12

20-23

14

Moving cast shadow detection using block nonnegative matrix factorization

80%

Yang X. , Liu D. , Zhou D. , Yang R.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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tom Vol. 66, nr 2

229--234

EN

In recent years, moving cast shadow detection has become a critical challenge in improving the accuracy of moving object detection in video surveillance. In this paper, we propose two novel moving cast shadow detection methods based on nonnegative matrix factorization (NMF) and block nonnegative matrix factorization (BNMF). First, the algorithm of moving cast shadow detection using NMF is given and the key points such as the determination of moving shadow areas and the choice of discriminant function are specified. Then BNMF are introduced so that the new training samples and new classes can be added constantly with lower computational complexity. Finally, the improved shadow detection method is detailed described according to BNMF. The effectiveness of proposed methods is evaluated in various scenes. Experimental results demonstrate that the method achieves high detection rate and outperforms several state-of-the-art methods.

15

Distribution Networks State Estimation Based on Topological Contraction and Quality Tag

80%

Huang Y. , Liu D. , Xu W. , Yu W.

Przegląd Elektrotechniczny

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2012

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tom R. 88, nr 5b

1-6

EN

By processing a set of raw measurement data, it provides a real-time system state solution which is the basis of the advanced applications. Currently, the incomplete and poor quality of measurement data is the key factor to impacting state estimation of distribution network. With the help of decision tree theory, the bad data identification method which combines the historical data and remote data from IDP (Integrated Data Platform) and a data processing method is proposed. Algorithm uses the laws of the distribution network data logic to determine the logic of the distribution network. With the help of the theoretical framework of decision tree we can establish the data quality assessment system and fix those bad data so as to increase the quality of the input data. On the basis of data evaluation and fixing, by collecting grid-based data of distribution network and using topology analysis and contracting technology, we can contract the actual network to the state estimation calculation network which meets the observation demand. Quality labels are used to modify the weight of the least squares state estimation algorithm to improve the accuracy of state estimation. Based on the status of data in city distribution network, a proper measurement data detecting and fixing method as well as topology contracting method is proposed. Two real cases of certain central power supply area in Shanghai have verified the effectiveness and feasibility of the method.

PL

W artykule zaproponowano metody badania stanu sieci dystrybucyjnej w czasie rzeczywistym. Metodę zilustrowano na przykładzie dwóch obszarów sieci zasilającej w Szanghaju.

16

Synthesis and Theoretical Studies of a New High Explosive, N,N,-Bis(3-aminofurazan-4-yl)-4,4´-diamino- 2,2´,3,3´,5,5´,6,6´-octanitroazobenzene

80%

Jing S. , Liu Y. , Liu D. , Guo J.

Central European Journal of Energetic Materials

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2015

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tom Vol. 12, no. 4

745--755

EN

A new high energy, low sensitivity material N,N,-bis(3-aminofurazan- 4-yl)-4,4´-diamino-2,2´,3,3´,5,5´,6,6´-octanitroazobenzene (BAFDAONAB) was synthesized from 4-chlorobenzoic acid and diaminofurazan. The structure of BAFDAONAB was characterized by FT-IR, NMR and Elemental Analyses and its purity was determined by HPLC. The optimized structure and thermodynamic parameters were obtained at the DFT- B3LYP/6-31+G** theoretical level. Its detonation properties were also predicted by the formulae of Kamlet-Jacobs and the Monte-Carlo method. The results show that the density, heat of formation, detonation velocity, detonation pressure, impact sensitivity and purity were 1.93 g/cm3, 4487.44 kJ/mol, 9.01 km/s, 35.03 GPa, 63 cm and 99.3%, respectively. In addition, the compound was an insensitive high explosive which could meet the requirements of high energetic materials.

17

Modelling suitable habitat and ecological characteristics of old trees using DIVA-GIS in Anhui Province, China

80%

Xie C. , Yu X. , Liu D. , Fang Y.

Polish Journal of Environmental Studies

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2020

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tom 29

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nr 2

18

Cadmium accumulation and its effects on growth and gas exchange in four populus cultivars

80%

Gu J. , Qi L. , Jiang W. , Liu D.

Acta Biologica Cracoviensia. Series Botanica

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2007

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tom 49

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nr 2

7-14

19

Nutrient resorption and use efficiency at different canopy heights of Alpine tree species Abies georgei var. smithii (Viguie et Gaussen) Cheng, Tibetan Plateau

80%

Li M. , Liu D. , Kong G.

Polish Journal of Ecology

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2009

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tom Vol. 57, nr 1

63-72

EN

Nutrients may be mobilized from senescing leaves and transported to other plant tissues, enabling plants to conserve them and reuse. Nitrogen and phosphorus are two dominant nutrients related to photosynthetic capacity and limiting plant growth. In this study, we examined the effect of canopy height on nutrient use by analyzing N and P concentrations of green and senescent leaves collected from different canopy heights of Abies georgei var. smithii (Viguie et Gaussen) Cheng growing at the alpine timberline in Sergyemla Mt.(4 350 m a.s.l), southeastern Tibetan Plateau. The results showed that N and P concentrations per unit needle mass decreased significantly with needle age, but no significant difference was found among upper, middle and lower canopy. However, area-based N and P concentrations increased with the height of canopy. The leaf level nutrient resorption and use efficiency varied in the order: upper canopy> middle canopy >lower canopy for both N and P. The higher nutrient resorption efficiency had significant relationship with leaf level nutrient use efficiency, that is, higher leaf level nutrient use efficiency was partly due to the high resorption from senescent needles. Additionally, the higher nutrient resorption was related to high current nutrient concentration. Vertical variations of leaf level nutrient use efficiency in this study reflected the strategy of alpine trees to respond to imbalance between light availability and soil nutrients.

20

Research on a New Synthesis of LLM-105 Using N-Nitroso-bis(cyanomethyl)amine

80%

Jing S. , Liu Y. , Liu D. , Guo J.

Central European Journal of Energetic Materials

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2016

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tom Vol. 13, no. 1

21--32

EN

A new three-step synthetic method was designed to prepare 2,6-diamino- 3,5-dinitropyrazine 1-oxide (LLM-105) with an overall yield of 43.5%, using iminodiacetonitrile, triethylamine and hydroxylamine hydrochloride as the starting materials, and involved nitrosylation, cyclization and nitration. The structure of LLM-105 was characterized by FTIR, 1H NMR spectroscopy and elemental analysis. The crucial factors and mechanism of the cyclization were explored. Thermal decomposition, mechanical sensitivity and the purity of the LLM-105 were determined by TG-DTA, an impact sensitivity instrument and high performance liquid chromatography (HPLC) respectively. The results showed that LLM-105 synthesised via 2,6-diamino-3,5-dinitropyrazine (ANPZ) was less sensitive to impact, but the LLM-105 synthesized by the new method had some obvious advantages in terms of purity, security and production costs. Moreover, the LLM-105 synthesized by this new method can be initiated reliably without recrystallization.