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Wyświetlanie 1-15 z 124
Tytuł:
Identification of Water Traffic Black Spot
Autorzy:
Chen, H.
Du, S.
Powiązania:
https://bibliotekanauki.pl/articles/359801.pdf
Data publikacji:
2013
Wydawca:
Akademia Morska w Szczecinie. Wydawnictwo AMSz
Tematy:
water traffic
control methods
water area
traffic accidents
algorithms
Opis:
Through defining Water Traffic Black Spot and analyzing the advantages and disadvantages of identification methods of Road Traffic Black Spot, then choosing Quality Control Method to recognize water area of intensive traffic accidents and applying integrated influential intensity of accident rate based on Systematical Clustering Algorithm into defining the boundary of the area, an effective evaluation method of black spot identification that is established, which lays a foundation for the subsequent evaluation work.
Źródło:
Zeszyty Naukowe Akademii Morskiej w Szczecinie; 2013, 36 (108) z. 1; 38-41
1733-8670
2392-0378
Pojawia się w:
Zeszyty Naukowe Akademii Morskiej w Szczecinie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physiological acclimation of Dicranostigma henanensis to soil drought stress and rewatering
Autorzy:
Wang, N.
Chen, H.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/2130560.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
Dicranostigma henanensis
drought stress
physiological changes
photosynthesis
rewatering
Opis:
e adaptability of plants to drought not only includes their ability to resist drought stress, but also their ability to recover aer stress is relieved. In this study, a weighting method was used to control the soil water content to produce a soil water stress gradient. e effects of drought and rewatering on the changes in osmotic adjustment substance content, antioxidant enzyme activity, and photosynthetic characteristics of potted Dicranostigma henanensis seedlings were measured on Day 28 aer the imposition of watering treatments and Day 7 aer rewatering. During the drought stress process, the relative electrical conductivity, thiobarbituric acid, water use efficiency, and proline content displayed a continuously increasing trend. Further, the net photosynthetic rate, stomatal conductance, and transpiration rate constantly decreased, while the chlorophyll content first increased and then decreased. Aer rehydration, superoxide dismutase (EC 1.15.1.1) activity and photosynthetic parameters quickly recovered to the CK level (soil moisture is 75%–80% of the maximum water holding capacity in the field), indicating that D. henanensis plants have a strong ability to repair the damage caused by drought stress. In particular, the photosynthetic machinery may have sophisticated regulation and repair mechanisms, which may be associated with its stable photosystem. Collectively, our findings demonstrate that the D. henanensis plant has a strong ability to adapt to arid environments, and therefore could be an excellent ornamental flower for landscaping in arid and semiarid areas.
Źródło:
Acta Societatis Botanicorum Poloniae; 2021, 90
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of waste heat recovery systems on energy efficiency improvement of a heavy-duty diesel engine
Autorzy:
Ma, Z.
Chen, H.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/240819.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
energy efficiency design index
energy efficiency operational indicator
waste heat recovery system
performance analysis
reduction factor
wskaźnik efektywności energetycznej
wskaźniki eksploatacyjny efektywności energetycznej
system odzysku ciepła odpadowego
analiza wydajności
współczynnik redukcyjny
Opis:
The increase of ship’s energy utilization efficiency and the reduction of greenhouse gas emissions have been high lightened in recent years and have become an increasingly important subject for ship designers and owners. The International Maritime Organization (IMO) is seeking measures to reduce the CO2 emissions from ships, and their proposed energy efficiency design index (EEDI) and energy efficiency operational indicator (EEOI) aim at ensuring that future vessels will be more efficient. Waste heat recovery can be employed not only to improve energy utilization efficiency but also to reduce greenhouse gas emissions. In this paper, a typical conceptual large container ship employing a low speed marine diesel engine as the main propulsion machinery is introduced and three possible types of waste heat recovery systems are designed. To calculate the EEDI and EEOI of the given large container ship, two software packages are developed. From the viewpoint of operation and maintenance, lowering the ship speed and improving container load rate can greatly reduce EEOI and further reduce total fuel consumption. Although the large container ship itself can reach the IMO requirements of EEDI at the first stage with a reduction factor 10% under the reference line value, the proposed waste heat recovery systems can improve the ship EEDI reduction factor to 20% under the reference line value.
Źródło:
Archives of Thermodynamics; 2017, 38, 3; 63-75
1231-0956
2083-6023
Pojawia się w:
Archives of Thermodynamics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of evaluation system of coastline resource in Dafeng
Autorzy:
Chen, M.
Xu, C.
Chen, H.
Powiązania:
https://bibliotekanauki.pl/articles/259978.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
coastline
Analytic Hierarchy Process
evaluation system
Opis:
Coastline is one type of valuable non-renewable resources. From the perspective of economic theory, it can gather population, promote traffic construction, and then improve the level of international trade. The research object of this paper is the coastline resource in Dafeng area. Firstly, we have a brief summary of the existing coastline evaluation literature, then introduce the location and natural attributes of the coastline resources in Dafeng. Following that, the Analytic Hierarchy Process (AHP) model is used to build the economic evaluation index system based on the characteristics of coastline in Dafeng. Specially, this index system consists of 6 factors, and a total of 41 detailed indicators were chosen including water depth, GDP, etc. On this basis, we use the assignment method to quantify the weight of each index, and calculate the comprehensive score of coastline resource by using the YAAHP software. The final conclusion is as follows: The total score of economic evaluation of coastline resource in Dafeng is 0.87. Therefore, the coastline resource in Dafeng will eventually be constructed a unique coastal economic zone, where the implemented port industrial projects will include shipbuilding, logistics, mechanical processing etc.
Źródło:
Polish Maritime Research; 2017, S 2; 181-187
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wave propagation in piezoelectric rings with rectangular cross-sections
Autorzy:
Zhang, X.
Wang, Y.
Chen, H.
Powiązania:
https://bibliotekanauki.pl/articles/279995.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
piezoelectric rings
orthogonal polynomial
guided wave
dispersion curves
Opis:
The ring ultrasonic transducers are widely used in the ocean engineering and medical fields. This paper employs an extended orthogonal polynomial approach to solve the guided wave propagation in two-dimensional structures, i.e. piezoelectric rings with rectangular cross- -sections. The extended polynomial approach can overcome the drawbacks of the conven- tional orthogonal polynomial approach which can be used to solve wave propagation in one-dimensional structures. Through numerical comparison with the available results for a rectangular aluminum bar, the validity of the present approach is illustrated. The dispersion curves and displacement and electric potential distributions of various rectangular piezo- electric rings are calculated, and the effects of different radius to thickness ratios, width to height ratios and polarizing directions on the dispersion curves are illustrated.
Źródło:
Journal of Theoretical and Applied Mechanics; 2015, 53, 3; 673-682
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the Creep Properties of Nonwoven Fabric with Mechanical Models
Analiza właściwości pełzania włóknin z zastosowaniem modelu mechanicznego
Autorzy:
Gao, X.
Chen, H.
Sun, S.
Powiązania:
https://bibliotekanauki.pl/articles/231630.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
nonwoven fabric
viscoelasticity
creep
mechanical model
nonlinear regression
włókniny i geowłókniny
lepkosprężystość
właściwości pełzania
model mechaniczny
regresja nieliniowa
Opis:
Since nonwoven fabric is widely used in the application of high performance geotextiles, its creep behaviour is essential to be evaluated. In this paper, the creep response of nonwven fabric was studied by using four mechanical models including the one-term generalised Kelvin model, Burger’s model, two-term generalised Kelvin model and Zurek’s model. To verify the feasibility of the models, creep experiments for nonwoven fabric were conducted, and the data were fitted by the four models, respectively, to obtain their parameter values using the Marquardt algorithm for nonlinear regression. When comparing the experimental creep curves with those fitted from the mechanical models, it is obvious that the experimental data was best fitted by Burger’s model. Also, since the residual sum of squares is far less than that of the GK (n = 1) and GK (n = 2) model and the squares of the correlation coefficient are near to unity, it can be concluded that Burger’s model is suitable to describe the creep behaviour of nonwoven fabric. Therefore the viscoelastic model verified can be adopted to predict the creep elongation of nonwoven fabrics.
W artykule zaprezentowano możliwość zastosowania modeli reologicznych do modelowania zjawiska pełzania włóknin. Włókniny i geowłókniny znajdują szerokie zastosowanie w inżynierii lądowej. Zjawiska jakie zachodzą podczas użytkowania geowłóknin są złożone. Jednym ze zjawisk pojawiających się podczas użytkowania jest poddawanie włókniny i geowłókniny stałym napięciom wynikającym ze zjawiska pełzania. Zastosowano trzy rodzaje modeli reologicznych w oparciu o modele Kelvina, Burgersa i uogólnionego modelu Kelvina. Wygenerowane modele teoretyczne zostały utworzone w celu przewidywania zjawiska pełzania. Adekwatność modeli reologicznych przeprowadzono w oparciu o metodę najmniejszych kwadratów dla estymacji parametrów w nieliniowych modelach regresji Levenberga - Marquardta. Zastosowano modele, które można dopasowywać przy pomocy estymacji metodą najmniejszych kwadratów dowolnej funkcji straty określonej przez użytkownika. Zastosowano funkcję straty do wyboru procedury estymacji, tak że praktycznie we wszystkich przypadkach otrzymano stabilne oceny parametrów modeli. Najlepsze efekty otrzymano przy zastosowaniu modelu Burgersa, który to może być użyty do przewidywania pełzania włókniny w obiektach inżynierskich.
Źródło:
Fibres & Textiles in Eastern Europe; 2015, 1 (109); 72-76
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational simulation analysis for torus radius of edge contact in hip prostheses
Autorzy:
Li, F.
Chen, H
Mao, K.
Powiązania:
https://bibliotekanauki.pl/articles/307414.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
staw biodrowy
endoproteza
kontakt Hertza
nacisk kontaktowy
hip prostheses
Hertzian contact
edge torus radius
contact pressure
contact dimensions
inclination angle
Opis:
Stripe wear occurs when the components of hip prostheses move a sufficient distance laterally to contact the edge of the acetabular cup, causing abnormally high contact stresses. In this research, edge loading contact of prosthetic hip is analyzed in the most commonly used material pairs. The contact dimensions and maximal contact pressure are investigated in mutative normal edge loading with 3 different inclination angles (15°, 20°, 25°) and in alterable edge torus radius with edge loading of 2500 N and inclination of 20°. A computational case was conducted for a 14 mm radius alumina ceramic bearing with a radial clearance of 0.1 mm using a normal edge loading ranged from 0 N to 3000 N. Additionally, the Hertzian theory successfully captures principal curvature trends of the edge torus on the influence of maximal contact pressure and obtains the appropriate edge radius range for lower maximal contact pressure. This work elucidates the methods of applying classical contact theory to design the edge radius of hip bearings to better resist severe edge loading contact stresses and reduce the stripe wear.
Źródło:
Acta of Bioengineering and Biomechanics; 2015, 17, 3; 67-73
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
3D laser scanning technique for the inspection and monitoring of railway tunnels
Technika skanowania laserowego 3D do kontroli i monitorowania tuneli kolejowych
Autorzy:
Chen, H-M.
Ulianov, C.
Shaltout, R.
Powiązania:
https://bibliotekanauki.pl/articles/375282.pdf
Data publikacji:
2015
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
railway tunnel
inspection of railway tunnels
monitoring of railway tunnels
laser scanning
tunel kolejowy
inspekcja tuneli kolejowych
monitorowanie tuneli kolejowych
skanowanie laserowe
Opis:
Railway tunnel inspection and monitoring has predominantly been a visual and manual procedure, which is time-consuming and subjective, giving rise to variance in standards and quality. Thus, alternative, novel, automated techniques need to be developed, for more efficient and reliable tunnel examination. The reported research aimed to investigate the application of a laser scanning technique for the inspection of tunnel degradation and structural integrity. The proposed method may either substitute or supplement traditional survey techniques, being more efficient, and contributing thus to the standardisation of tunnel inspections. For the purpose of investigating the applicability and accuracy of laser scanning in tunnels, a set of tunnel lining models was constructed for laboratory tests, with the objective of determining the quality of the imaging. Initial tests were carried out using a performant laser scanner and demonstrated the feasibility of the concept. As a result, refined laboratory models were built, and experiments conducted, to establish the quality and precision of laser scanning imaging, for condition monitoring of tunnels. The experimental results indicate that the laser scanning technique used in this research has high potential for detecting the tunnel condition, monitoring the depth of weathered mortar, spalling bricks etc. with high accuracy in static scanning mode.
Kontrola i monitoring tuneli kolejowych w przeważającej mierze to procedura, która jest czasochłonna i subiektywna, co powoduje zróżnicowanie standardów i jakości badań. Stąd też muszą być opracowane alternatywe, nowoczesne, zautomatyzowane techniki do bardziej skutecznych i rzetelnych badań. Przedstawione badania miały na celu wskazanie zastosowania techniki skanowania laserowego do kontroli degradacji tunelu i integralności strukturalnej. Proponowana metoda może zastąpić, bądź uzupełnienić, tradycyjne techniki pomiarowe. Jest ona bardziej wydajna i może przyczynić się do standaryzacji kontroli tuneli. Aby zbadać przydatności i dokładności skanowania laserowego w tunelach, skonstruowano zestaw modeli do testów labolatoryjnych, w celu określenia jakości obrazów. Wyniki doświadczalne wskazują, że technika skanowania laserowego zastosowana w badaniu ma wysoki potencjał do charakteryzowania stanu tunelu, monitorowania głębokości zwietrzenia zaprawy, odpryskiwania cegieł itp., z dużą dokładnością w trybie statycznym skanowania.
Źródło:
Transport Problems; 2015, T. 10, z. spec.; 73-84
1896-0596
2300-861X
Pojawia się w:
Transport Problems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Separation of matrine and oxymatrine from Sophora flavescens extract through cation exchange resin coupled with macroporous absorption resin
Autorzy:
Chen, H.
Luo, S.
Zheng, X.
Fan, H.
Powiązania:
https://bibliotekanauki.pl/articles/778382.pdf
Data publikacji:
2016
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Sophora flavescens
BS-65 macroporous resin
001×732 cation exchange resin
separation
alkaloids
Opis:
A simple method for separation of matrine and oxymatrine from Sophora flavescens was developed with cation exchange resin coupled with macroporous resin. Based on the adsorption characteristics of matrine and oxymatrine, 001×732 cation exchange resin was used to absorb target alkaloids for removing most of the foreign matter, while BS-65 macroporous resin was chosen to purify these alkaloids. The result showed that the equilibrium adsorption data of matrine and oxymatrine on 001×732 resin and BS-65 resin at 30°C was fitted to Langmuir isotherm and Freundlich isotherm, respectively. The contents of matrine and oxymatrine were increased from 0.73% and 2.2% in the crude extract of the root of Sophora flavescens to 67.2% and 66.8% in the final eluent products with the recoveries of 90.3% and 86.9%, respectively.
Źródło:
Polish Journal of Chemical Technology; 2016, 18, 2; 31-39
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compositions of Al-Based Quasicrystals Interpreted by Cluster Formulae
Autorzy:
Chen, H.
Qiang, J.
Wang, Y.
Dong, C.
Powiązania:
https://bibliotekanauki.pl/articles/1372748.pdf
Data publikacji:
2014-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.44.Br
36.40.-c
71.20.Lp
Opis:
It is known previously that bulk metallic glass compositions satisfy cluster formulae $[cluster](glue atom)_{1, 3}$ of 24 valence electrons as deduced from our cluster-resonance model. In the present work, it is further shown that compositions of Al-based binary and ternary quasicrystals are also explained by 24-electron cluster formulae of the types $[icosahedron](glue atom)_{0, 1}$, where the icosahedral cluster is identified from a corresponding crystalline approximant according to dense atomic packing and cluster isolation criteria, and the glue atom site is either vacant for an icosahedral quasicrystal or equal to one for a decagonal quasicrystal. Ternary quasicrystals are formulated with the same formulae as their basic binary ones but the icosahedron shell sites are substituted by third elements. The 24-electron cluster formulae are then the chemical and electronic structural units of quasicrystals, mimicking the molecular formulae of chemical substances.
Źródło:
Acta Physica Polonica A; 2014, 126, 2; 446-448
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Current Injection Attack against the KLJN Secure Key Exchange
Autorzy:
Chen, H.-P.
Mohammad, M.
Kish, L. B.
Powiązania:
https://bibliotekanauki.pl/articles/220991.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
KLJN
current injection attack
secure key exchange
unconditional security
privacy amplification
Opis:
The Kirchhoff-law-Johnson-noise (KLJN) scheme is a statistical/physical secure key exchange system based on the laws of classical statistical physics to provide unconditional security. We used the LTSPICE industrial cable and circuit simulator to emulate one of the major active (invasive) attacks, the current injection attack, against the ideal and a practical KLJN system, respectively. We show that two security enhancement techniques, namely, the instantaneous voltage/current comparison method, and a simple privacy amplification scheme, independently and effectively eliminate the information leak and successfully preserve the system’s unconditional security.
Źródło:
Metrology and Measurement Systems; 2016, 23, 2; 173-181
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
2D Structural Acoustic Analysis Using the FEM/FMBEM with Different Coupled Element Types
Autorzy:
Chen, L.
Zhao, W.
Liu, C.
Chen, H.
Powiązania:
https://bibliotekanauki.pl/articles/176330.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
boundary element method
finite element method
discontinuous boundary elements
acoustic fluid-structure interaction
fast multipole method
Opis:
A FEM-BEM coupling approach is used for acoustic fluid-structure interaction analysis. The FEM is used to model the structure and the BEM is used to model the exterior acoustic domain. The aim of this work is to improve the computational efficiency and accuracy of the conventional FEM-BEM coupling approach. The fast multipole method (FMM) is applied to accelerating the matrix-vector products in BEM. The Burton-Miller formulation is used to overcome the fictitious eigen-frequency problem when using a single Helmholtz boundary integral equation for exterior acoustic problems. The continuous higher order boundary elements and discontinuous higher order boundary elements for 2D problem are developed in this work to achieve higher accuracy in the coupling analysis. The performance for coupled element types is compared via a simple example with analytical solution, and the optimal element type is obtained. Numerical examples are presented to show the relative errors of different coupled element types.
Źródło:
Archives of Acoustics; 2017, 42, 1; 37-48
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Neural network based identification of hysteresis in human meridian systems
Autorzy:
Tan, Y.
Dong, R.
Chen, H.
He, H.
Powiązania:
https://bibliotekanauki.pl/articles/330958.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
punkt akupunktury
histereza
sieć neuronowa
tradycyjna medycyna chińska
acupuncture point
hysteresis
identification
neural network
human meridian
traditional Chinese medicine
Opis:
Developing a model based digital human meridian system is one of the interesting ways of understanding and improving acupuncture treatment, safety analysis for acupuncture operation, doctor training, or treatment scheme evaluation. In accomplishing this task, how to construct a proper model to describe the behavior of human meridian systems is one of the very important issues. From experiments, it has been found that the hysteresis phenomenon occurs in the relations between stimulation input and the corresponding response of meridian systems. Therefore, the modeling of hysteresis in a human meridian system is an unavoidable task for the construction of model based digital human meridian systems. As hysteresis is a nonsmooth, nonlinear and dynamic system with a multi-valued mapping, the conventional identification method is difficult to be employed to model its behavior directly. In this paper, a neural network based identification method of hysteresis occurring in human meridian systems is presented. In this modeling scheme, an expanded input space is constructed to transform the multi-valued mapping of hysteresis into a one-to-one mapping. For this purpose, a modified hysteretic operator is proposed to handle the extremum-missing problem. Then, based on the constructed expanded input space with the modified hysteretic operator, the so-called Extreme Learning Machine (ELM) neural network is utilized to model hysteresis inherent in human meridian systems. As hysteresis in meridian system is a dynamic system, a dynamic ELM neural network is developed. In the proposed dynamic ELMneural network, the output state of each hidden neuron is fed back to its own input to describe the dynamic behavior of hysteresis. The training of the recurrent ELM neural network is based on the least-squares algorithm with QR decomposition.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2012, 22, 3; 685-694
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Positron Annilation Lifetime and Glass Transition Temperatures in $CO_2$ Sorption Polystyrene
Autorzy:
Jean, Y.
Chen, H.
Lee, L.
Yang, J.
Powiązania:
https://bibliotekanauki.pl/articles/1812530.pdf
Data publikacji:
2008-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.70.Bj
78.66.Qn
71.60.+z
Opis:
Positron annihilation lifetime spectroscopy was used to measure the free-volume size and distributions as a function of temperature in polystyrene with and without 400 psi $CO_2$ sorption. The transition temperatures in the polystyrene with $CO_2$ sorption obtained from ortho-positronium lifetimes were found to depend on the thermal cycles and a meta-stable state showing a negative thermal expansion coefficient was observed between 53°C and 82°C during the first heating up experiment. The observed $T_g$ in polystyrene with, and without $CO_2$ sorption after annealing from ortho-positronium lifetimes were found to be 86°C and 91°C, which are 5°C higher, and 10°C lower than from the differential scanning calorimetry data, respectively. The observed free-volume variations are discussed in terms of hole expansion, creation, free-volume relaxation, plasticization, and hole filling in amorphous polymers.
Źródło:
Acta Physica Polonica A; 2008, 113, 5; 1385-1395
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Floral scent compounds and emission patterns of three Styrax species
Autorzy:
Chen, C.
Cao, Y.
Chen, H.
Ni, M.
Yu, F.
Powiązania:
https://bibliotekanauki.pl/articles/2078258.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
Styrax species
volatile compounds
terpenes
SPME-GC/MS
Opis:
Styrax is a gorgeous species combined with high medicinal and ornamental values, however, in- formation about its floral scents is limited. This study aimed to reveal the floral scent compounds and the dynamic changes in the flowering process of Styrax japonicus, S. grandiflora and S. calvescens. Static headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry was adopted in the pres- ent study. The results showed that 24, 22 and 22 volatile compounds were present at three flowering stages, among which linalool, ocimene, α-pinene and germacrene D dominated in different species. Terpenes were the main floral scent compounds in all species, whereas there was considerable relative content of ketones in S. japonicus. Among the major terpenes, α-pinene, ocimene and myrcene were the common volatiles in these species, while β-elemene and allo-ocimene were the specific volatiles in S. japonicus and S. calvescens, respec- tively. The highest content of terpenes occurred at initial flowering stage in three species. The differences in the type and content of principal compounds contributed to the fragrance diversity among these species. A solid foundation for understanding the complexity of volatile emission could be obtained from our findings, meanwhile, effective utilization of abundant terpenes in flowers of Styrax species should be applied.
Źródło:
Dendrobiology; 2021, 85; 30-38
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 124

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