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Wyszukujesz frazę "Li, J. B." wg kryterium: Autor


Tytuł:
Experimental and numerical study of the uniaxial compressive stress-strain relationship of a rock mass with two parallel joints
Autorzy:
Xiong, L. X.
Yuan, H. Y.
Zhang, Y.
Zhang, K. F.
Li, J. B.
Powiązania:
https://bibliotekanauki.pl/articles/231076.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
masa skalna łączona
złącze równoległe
siła szczytowa
jointed rock mass
parallel joint
peak strength
Opis:
A “rock bridge”, defined as the closest distance between two joints in a rock mass, is an important feature affecting the jointed rock mass strength. Artificial jointed rock specimens with two parallel joint fractures were tested under uniaxial compression and numerical simulations were carried out to study the effects of the inclination of the rock bridge, the dip angle of the joint, rock bridge length, and the length of joints on the strength of the jointed rock mass. Research results show: (1) When the length of the joint fracture, the length of the rock bridge, and the inclination of the rock bridge stay unchanged, the uniaxial compressive strength of the specimen gradually increases as the inclination of the joint fracture increases from 0° to 90°. (2) When the length of the joint fracture, the length of the rock bridge, and the inclination of the joint fracture stay unchanged, the uniaxial compressive strength of the specimen shows variations in trends with the inclination of the rock bridge increasing from 30° to 150° (3). In the case when the joint is angled from the vertical loading direction, when the dip angle of the joint fracture, the inclination of the rock bridge, and the length of the rock bridge stay unchanged, the uniaxial compressive strength of the specimen gradually decreases with an increasing length of joint fracture. When the dip angle of the joint fracture, the inclination of the rock bridge, and the length of the joint fracture stay unchanged, the uniaxial compressive strength of the specimen does not show a clear trend with an increase of the length of the rock bridge.
Źródło:
Archives of Civil Engineering; 2019, 65, 2; 67-80
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ISSR analysis of somaclonal variation in callus-derived plants of Amorphophallus rivieri Durieu
Autorzy:
Hu, J.B.
Li, Q.
Li, J.
Powiązania:
https://bibliotekanauki.pl/articles/19740.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
somaclonal variation
callus-derived plant
Amorphophallus rivieri
ISSR technique
regenerated plant
plant cultivation
crop
China
Opis:
This communication reports detection of somaclonal variation among tissue culture-raised plants of Amorphophallus rivieri Durieu, an economically important crop in China, with high content of glucomannan in its corms. A population of regenerated plants was obtained from a single donor plant of A. rivieri via corm organogenesis, and 28 plants were randomly selected as a representative sample and subjected to analysis of somaclonal variation using inter-simple sequence repeat (ISSR) markers. Of the 26 ISSR primers screened, 13 gave distinct and reproducible band patterns, yielding 131 bands with an average of 10.1 bands per primer. Ten primers were polymorphic and generated 16 polymorphic bands with 12.2% mean polymorphism. Based on the ISSR data from the regenerated plants and the donor plant, Jaccard's similarity coefficients were calculated; they ranged from 0.961 to 1.000 with a mean of 0.982. A dendrogram was constructed using the unweighted pair group method with arithmetic mean (UPGMA); it showed that a majority of regenerated plants (including the donor plant) clustered closely, with a mean similarity coefficient of 0.987. Low somaclonal variation observed in the regenerated plants indicates that rapid propagation of A. rivieri via corm organogenesis is a practicable method with a low risk of genetic instability.
Źródło:
Acta Biologica Cracoviensia. Series Botanica; 2011, 53, 1
0001-5296
Pojawia się w:
Acta Biologica Cracoviensia. Series Botanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New basal synapsid supports Laurasian origin for therapsids
Autorzy:
Liu, J
Rubidge, B.
Li, J.
Powiązania:
https://bibliotekanauki.pl/articles/21774.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
synapsid
Laurasia
therapsid
fossil
paleontology
China
Therapsida
Dashankou
Permian
fauna
Gansu province
tetrapod fossil
Opis:
The distant evolutionary ancestry of mammals is documented by a rich therapsid fossil record. While sphenacodontid synapsids are considered the sister−group of therapsids, the place of origin of therapsids is an enigma, largely because of a long standing morphological and temporal gap (Olson’s Gap) in their fossil record. We describe a new large predatory synapsid, Raranimus dashankouensis gen. et sp. nov., from the Middle Permian of Dashankou in China which has a unique combination of therapsid and sphenacodontid features. This specimen is of great significance asit is a basal therapsid which is the sister taxon to all other therapsids. The fact that it was found in association with Early Permian tetrapods (Anakamacops and Belebey) suggests that it is the oldest therapsid and provides the first evidence of therapsid−bearing rocks which cover Olson’s Gap. It further supports that therapsids may have had a Laurasian rather than Gondwanan origin.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 3; 393-400
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An ant-based filtering random-finite-set approach to simultaneous localization and mapping
Autorzy:
Li, D.
Zhu, J.
Xu, B.
Lu, M.
Li, M.
Powiązania:
https://bibliotekanauki.pl/articles/329854.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
simultaneous localization
simultaneous mapping
random finite set
probability hypothesis density
ant colony
lokalizacja jednoczesna
mapowanie jednoczesne
algorytm mrówkowy
Opis:
Inspired by ant foraging, as well as modeling of the feature map and measurements as random finite sets, a novel formulation in an ant colony framework is proposed to jointly estimate the map and the vehicle trajectory so as to solve a feature-based simultaneous localization and mapping (SLAM) problem. This so-called ant-PHD-SLAM algorithm allows decomposing the recursion for the joint map-trajectory posterior density into a jointly propagated posterior density of the vehicle trajectory and the posterior density of the feature map conditioned on the vehicle trajectory. More specifically, an ant-PHD filter is proposed to jointly estimate the number of map features and their locations, namely, using the powerful search ability and collective cooperation of ants to complete the PHD-SLAM filter time prediction and data update process. Meanwhile, a novel fast moving ant estimator (F-MAE) is utilized to estimate the maneuvering vehicle trajectory. Evaluation and comparison using several numerical examples show a performance improvement over recently reported approaches. Moreover, the experimental results based on the robot operation system (ROS) platform validate the consistency with the results obtained from numerical simulations.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2018, 28, 3; 505-519
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compressive optical image encryption using phase-shifting interferometry on a joint transform correlator
Autorzy:
Li, J.
Jia, B.
Dai, X.
Lei, M.
Yang, C.
Li, H.
Li, R.
Powiązania:
https://bibliotekanauki.pl/articles/174905.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
fully optical system
holographic interferometry
joint transform correlator (JTC)
binary scrambling method
inverse problems
Opis:
A compressive optical image encryption method, which combines compressive sensing with phase-shifting interferometry on a joint transform correlator, is proposed in the fully optical domain. The object image is first permutated using a binary scrambling method. Next, the permutated object field is encrypted and registered as the holograms by phase-shifting interferometry on the joint transform correlator setup. Then, the encrypted images and the key are compressed to the compressed data using single-pixel compressive imaging. The original image can be reconstructed and decrypted using the specified algorithm. The simulations demonstrate that the method is effective and suitable for image security transmission.
Źródło:
Optica Applicata; 2017, 47, 2; 245-256
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sensitive detection of acetylene by second derivative spectra with tunable diode laser absorption spectroscopy
Autorzy:
Deng, H.
Sun, J.
Li, P.
Liu, Y.
Yu, B.
Li, J.
Powiązania:
https://bibliotekanauki.pl/articles/174963.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tunable diode laser absorption spectroscopy
TDLAS
signal processing
Savitzky–Golay filter
trace gas detection
Opis:
A tunable diode laser absorption spectrometer was developed for trace acetylene gas analysis, the system performance was evaluated by combing an appropriate digital signal processing methods, i.e., Savitzky–Golay smoothing and differentiation algorithm. The calculation of the derivative spectra by this method is accompanied by simultaneous data smoothing. Based on the 2nd deriv- ative spectra detection method, the Allan variance technique indicates a C2H2 detection limit of 1.7ppm for 1-s averaging time, and a minimum noise level of 62ppb (parts per billion), at the optimum integration time of ~60s. The calculated 2nd derivative spectra with better resolution, lower detection limits, save signal processing time, and improve the ability to distinguish unresolved spectral signals.
Źródło:
Optica Applicata; 2016, 46, 3; 353-363
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the influence on expressway safety of ramps
Autorzy:
Hu, J. J.
Li, F.
Han, B.
Yao, J.
Powiązania:
https://bibliotekanauki.pl/articles/224137.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
expressway safety
safety
on and off ramp
delay
accidents occurrence probability
droga ekspresowa
bezpieczeństwo na drodze ekspresowej
rampa włączania i wyłączania
opóźnienie
prawdopodobieństwo wystąpienia awarii
Opis:
As the very important parts of the expressway system, on and off ramps have a great effect on the operation effect of expressways. Once congestion occurs at on and off ramps, it will directly affect the safety of the expressway and vehicles. So this paper first analyzes the location design of on ramps, the length and the influences on the expressway running state of off ramp downstream traffic state, and establishes the expressway operation models based at on and off ramps. The expressway operation models include off ramp delay model, on ramp delay model, expressway delay model and side road delay model under the influence of the distance between on and off ramp and traffic volume. At the same time, the paper analyzes the connection between the traffic operation state and traffic safety, and establishes the expressway safety model based on congestion degree. Through simulation verification, the impact of on and off ramp on the security of the expressway is analyzed. In the simulation, safety rank division is simulated to verify and safety index of different safety ranks. Finally the paper concludes that the delay caused by traffic of the on and off ramps can decrease the safety of expressway.
Źródło:
Archives of Transport; 2017, 43, 3; 43-51
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Polarization-independent metal-dielectric grating with improved bandwidth
Autorzy:
Wang, B
Li, H
Shu, W
Li, W
Li, C
Lei, L
Zhou, J
Powiązania:
https://bibliotekanauki.pl/articles/174684.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
rigorous coupled-wave analysis
reflective efficiency
improved bandwidth
Opis:
A polarization-independent reflective grating with improved bandwidth is presented based on the mixed metal-dielectric grating. The novel grating is composed of the substrate, the metal slab, two dielectric layers, and the covering layer. The grating parameters are optimized for the special duty cycle of 0.6 at an incident wavelength of 1550 nm used in dense wavelength division multiplexing (DWDM). With the designed grating, high efficiency can be diffracted into the reflective –1st order for both TE and TM polarizations, where the polarization-independence is exhibited. Most importantly, the efficiency of more than 90% can be achieved within the incident wavelength bandwidth of 1262–1686 nm, where the bandwidth is improved greatly compared with the reported surface-relief single-layer grating. The reflective grating can have advantages of high efficiency, polarization-independence, and wide bandwidth, which should be useful for DWDM applications.
Źródło:
Optica Applicata; 2015, 45, 1; 71-77
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Applying Image Analysis for Automatic Density Measurement of High-tightness Woven Fabrics
Zastosowanie analizy obrazu do automatycznej oceny gęstości tkanin o dużej zwartości
Autorzy:
Pan, R.
Zhang, J.
Li, Z.
Gao, W.
Xu, B.
Li, W.
Powiązania:
https://bibliotekanauki.pl/articles/232730.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
high-tightness woven fabric
image analysis
Fourier transform
threshold processing
image reconstruct
wysoka szczelność tkaniny
analiza obrazu
transformat Fouriera
rekonstrukcja obrazu
Opis:
To realise the density measurement of high-tightness woven fabrics, an efficient inspection method based on the structure relation is developed in this paper. The structure relations of typical HTWF, twill and satin weave are analyzed and a calculation equation of warp density is given with the fabric weave, weft density and wale density. In the experiment, the weft and wale densities are measured with the Fourier transform, image reconstruction and threshold processing based on separately captured images. The warp density is finally calculated based on the mean value of wale and weft density and the given calculation equation constructed with the weave pattern. The experimental results prove that the automatic measurement density system can realize the precise measurement of high-tightness woven fabric density with satisfactory precision and can replace the current manual analysis method.
Dla zrealizowania pomiarów gęstości tkanin o dużej zwartości opracowano metodę oceny opartą o zależności strukturalne. Zależności strukturalne typowych tkanin HTWF, o splocie skośnymi i satynowym analizowano i opracowano wzory dla obliczania gęstości osnowy, w zależności od gęstości wątku i gęstości prążków wypukłych. Przy przeprowadzeniu eksperymentu gęstości wątku i prążków wypukłych mierzono stosując transformatę Fouriera, rekonstrukcję obrazu i obliczenie wartości progowych wykorzystując indywidualnie otrzymane obrazy. Gęstość osnowy w efekcie jest obliczana w oparciu o średnią wartość gęstości prążków i wątku. Wyniki eksperymentalne potwierdziły, że automatyczny pomiar gęstości jest systemem, który może realizować precyzyjnie pomiar gęstości tkanin o dużej zwartości z zadowalającą dokładnością i w ten sposób może zastąpić dotychczas stosowane metody manualne.
Źródło:
Fibres & Textiles in Eastern Europe; 2016, 2 (116); 66-72
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Real-time Segmentation of Yarn Images Based on an FCM Algorithm and Intensity Gradient Analysis
Segmentacja obrazu przędzy oparta na algorytmie FCM i analizie gradientu intensywności
Autorzy:
Li, Z.
Pan, R.
Wang, J.
Wang, Z.
Li, B.
Gao, W.
Powiązania:
https://bibliotekanauki.pl/articles/233569.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
real-time segmentation
image processing
yarn evenness
FCM algorithm
gradient analysis
segmentacja w czasie rzeczywistym
przetwarzanie obrazu
algorytm FCM
analiza gradientu
Opis:
This paper presents a new method for real-time segmentation of yarn images which are captured by a real-time image acquisition device. The first frame of the images is clustered by the local average intensity and entropy of the image based on the FCM (Fuzzy C-means) algorithm to obtain a segmentation threshold value. The pixels with an intensity below the threshold value in each column of the image are convolved with a convolve template to construct an intensity gradient curve. The points of maximum value and minimum value in the curve are considered as the upper and lower edge points of yarn. A robust real-time segmentation algorithm of yarn images is obtained for evaluating yarn diameter more precisely. Finally two indices of SE (Segmentation Error) in % and ADE (Average Diameter Error) in % are proposed to evaluate the segmentation method, which is then compared with the manual method.
Artykuł dotyczy oceny przeprowadzonej w czasie rzeczywistym segmentacji obrazów w oparciu o rozmyty algorytm C-średnich i analizę intensywności gradientu. Zaproponowano metodę segmentacji obrazów przędzy mającą na celu zwiększenie dokładności pomiarów jej średnicy, a w zamierzeniach wpłynięcie na zwiększenie dokładności oceny jej nierównomierności. W tym celu zaprojektowano stanowisko badawcze, umożliwiające rejestrację obrazów przędzy wykonaną w czasie rzeczywistym, z bardzo dużą częstotliwością rejestracji kadrów zdjęć. Na tej podstawie przeprowadzono obliczenia obejmujące między innymi minimalizację rozmytej funkcji celu, lokalną charakterystykę intensywności obrazu, a także jednowymiarowy splot wykorzystane do wykrywania krawędzi rozpatrywanej przędzy. Uzyskane rezultaty proponowanej metody skonfrontowano z rezultatami przewidywanymi za pośrednictwem tradycyjnych metod. W szczególności w celach porównawczych uwzględniono progowanie Otsu i grupowanie za pośrednictwem algorytmu FCM, a także Region Growing Algorithm.
Źródło:
Fibres & Textiles in Eastern Europe; 2016, 4 (118); 45-50
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Galvanic contacting effect of pyrite on xanthate adsorption on galena surface: DFT simulation and cyclic voltammetric measurements
Autorzy:
Ke, B.
Chen, J.
Li, Y.
Chen, Y.
Powiązania:
https://bibliotekanauki.pl/articles/110904.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
adsorption
DFT
galvanic interaction
pyrite surface
galena surface
cyclic voltammetric measurements
Opis:
The effect of galvanic interaction between pyrite and galena on xanthate adsorbing on the galena surface has been investigated by means of density functional theory (DFT) and cyclic voltammetric measurements. The calculated results show that differences in the contact site and contact distance between galena and pyrite can affect the intensity of the galvanic interaction, and the relationship between the intensity of galvanic interaction and the adsorption ability of xanthate on galena surface has been studied in detail. In general, the galvanic interaction between pyrite and galena surface can enhance the adsorption of xanthate on the galena surface. The adsorption energies of xanthate on the galena surface decrease with the decrease of contact distance, and when the contact distance is lower than 4 Å, the adsorption energies decrease significantly at Pb-Pb, Pb-S and S-S sites. In particular, at the contact distance of 3 Å, a sharp decrease of adsorption energy is observed at the Pb-Pb contact site; in this case, the negative shift of the Pb-S bonding range and DOS non-locality at Pb-Pb contact site are significantly greater than that of the S-S or Pb-S contact sites. The cyclic voltammetric measurements reveal that the galvanic interaction between galena and pyrite improves the adsorption of xanthate on galena surface, which is in good agreement with the DFT results.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 3; 826-836
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Three-port beam splitter based on a sandwiched grating with an improved aspect ratio
Autorzy:
Shu, W
Wang, B
Li, H
Li, W
Chen, L.
Lei, L.
Zhou, J.
Powiązania:
https://bibliotekanauki.pl/articles/174445.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
aspect ratio
sandwiched grating
three-port beam splitter
Opis:
In this paper, a fused-silica transmission grating used as a three-port beam splitter is designed by using the rigorous coupled-wave analysis, which is based on the sandwiched grating structure at the wavelength of 800 nm under normal incidence. Firstly, it is feasible to realize such a grating with the prescribed grating duty cycle and grating period. Next, high efficiency can be also achieved for both TE and TM polarizations. Moreover, the aspect ratio of the grating depth to the ridge width can be improved, which is significant for practical applications. At last, the three-port beam splitter is designed with a covering layer on the surface, which can extend its life service.
Źródło:
Optica Applicata; 2015, 45, 3; 279-284
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculating study of the turbine at last stage flow field in the small volume flow condition
Autorzy:
Jiang, T.
Jin, J.
Wang, Z.
Cao, L.
Li, B.
Powiązania:
https://bibliotekanauki.pl/articles/258680.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
turbine
small volume flow
flow model
backflow
Opis:
Based on basic equation and boundary layer theory of pneumodynamics, the thesis conducts numerical modeling and theoretical analysis on the last stage of turbine characteristics at a small volume flow by using FLUENT, gives an emphasized analysis on the position of first occurrence of backflow and its expansion direction and comes up with flow structure of the turbine flow field at last stage in the small volume flow condition. In connection with specific experiments, it puts forward the flow model of backflow occurring in the last stage field and the solution to the model. The flow field at last stage for a 100MW turbine in the small volume flow condition that is calculated by using the model is basically in conformity to the actual result.
Źródło:
Polish Maritime Research; 2017, S 3; 23-27
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Insensitive Booster Explosive: DAAF Surface-coated with Viton A
Autorzy:
Li, X.
Wu, B.
Liu, S.
An, C.
Wang, J.
Powiązania:
https://bibliotekanauki.pl/articles/358841.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
DAAF
refinement
surface-coated
thermal analysis
impact sensitivity
Opis:
3,3’-Diamino-4,4’-azoxyfurazan (DAAF) is the principal component of an insensitive booster explosive; refined DAAF and DAAF surface-coated with Viton A were prepared. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimetry (DSC) were employed to characterize the morphology, composition, and thermal decomposition of these samples. The impact sensitivity and theoretical detonation velocity of DAAF-based composites were also measured and analyzed. The results showed that DAAF surface-coated with Viton A was successfully obtained, and the impact sensitivity of DAAF/Viton A composites was much lower than that of crude DAAF. In addition, DAAF/Viton A composites exhibited better thermal stability compared to crude DAAF and refined DAAF. The theoretical detonation velocity of DAAF/Viton A composites and TATB/Viton A composites are roughly the same. Therefore, there is still great potential for DAAF to be used as the main explosive component of a booster explosive.
Źródło:
Central European Journal of Energetic Materials; 2018, 15, 3; 445-455
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solution Growth of Well-Aligned ZnO Nanorods on Sapphire Substrate
Autorzy:
Jia, G.
Hao, B.
Lu, X.
Wang, X.
Li, Y.
Yao, J.
Powiązania:
https://bibliotekanauki.pl/articles/1399510.pdf
Data publikacji:
2013-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.37.Yz
78.40.Fy
68.55.J-
Opis:
Vertically well-aligned ZnO nanorods arrays were synthesized on sapphire substrates by chemical bath deposition. Those sapphire substrates were seeded to control the density and orientation of ZnO nanorods using sol-gel method. Well-aligned and uniformly distributed ZnO nanorods in a large scale were obtained with strongly (002) preferential orientation. The structural properties were characterized by X-ray diffraction spectrometer and morphological characteristics were analyzed by scanning electron microscopy, respectively. The ZnO nanorods are obvious hexangular wurtzite structure and preferentially oriented along the c-axis (002) and growth vertically to the substrates. The optical properties were further thoroughly studied. What is more, the influences of the strain between substrate and ZnO nanorods due to thickness of the ZnO seed-layer on the characteristics and optical properties of ZnO were also analyzed.
Źródło:
Acta Physica Polonica A; 2013, 124, 1; 74-77
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth of β-$Ga_2O_3$ Nanorods and Photoluminescence Properties
Autorzy:
Zhang,, S.
Zhuang, H.
Xue, C.
Li, B.
Shen, J.
Wang, D.
Powiązania:
https://bibliotekanauki.pl/articles/1814023.pdf
Data publikacji:
2007-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
68.65.-k
79.60.Jv
81.15.Cd
Opis:
β-$Ga_2O_3$ nanorods were successfully fabricated through annealing $Ga_2O_3$/Mo films deposited on the Si (111) substrate by radio frequency magnetron sputtering technique. The morphology and structure of the as-synthesized nanorods were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and energy dispersive X-rays spectroscopy. The results show that the formed nanorods are single-crystalline $Ga_2O_3$ with monoclinic structure. The diameters of nanorods are 200 nm and lengths typically up to several micrometers. A photoluminescence spectrum at room temperature under excitation at 325 nm exhibits two strong blue-light peaks located at about 413.0 nm and 437.5 nm, attributed to the recombination of bound electron-hole exciton in β-$Ga_2O_3$ single crystal. The growth process of the β-$Ga_2O_3$ nanorods is probably dominated by conventional vapor-solid mechanism.
Źródło:
Acta Physica Polonica A; 2007, 112, 6; 1195-1201
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical analysis of a hollow laser beam transmitting in an off-axis Cassegrain optical antenna system
Autorzy:
Mi, C
Jiang, P
Yang, H.
Ke, S
Li, B
Liu, J.
Powiązania:
https://bibliotekanauki.pl/articles/174358.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
Cassegrain optical antenna
off-axis hollow laser beam
receiving efficiency
Opis:
The optical model of a Cassegrain optical antenna with a confocal double-parabolic reflector structure has been designed, and the propagation characteristics of a hollow laser beam, which could avoid the loss of energy caused by the subreflector center reflection in the optical antenna, has been researched in this paper. By detailed analysis and numerical calculations of a receiving Cassegrain antenna with different deflection angles, the coupling efficiency curve and 3-D distributions of the receiving light intensity for different inclined angles have been obtained.
Źródło:
Optica Applicata; 2014, 44, 3; 421-431
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Highly-efficient three-port output by metal-mirror-based grating
Autorzy:
Li, H.
Wang, B.
Shu, W.
Chen, L.
Lei, L.
Zhou, J.
Powiązania:
https://bibliotekanauki.pl/articles/174526.pdf
Data publikacji:
2016
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
three-port output
metal-mirror-based grating
rigorous coupled-wave analysis
Opis:
A highly-efficient three-port output of metal-mirror-based grating is proposed in this paper. The metal-mirror-based grating can function as a beam splitter which can diffract the normal incident wave into the 0th and the +/- 1st orders for both TE and TM polarizations with the usual duty cycle of 0.5. The analysis of the grating parameters can be optimized by rigorous coupled-wave analysis. The high efficiency for TE and TM polarizations shall be realized. By means of the numerical simulation, the depth and connecting layer thickness of grating can be accurately calculated. The efficiency of per port is near 33.3%, so the novel three-port output grating with a connecting layer would be an excellent optical element.
Źródło:
Optica Applicata; 2016, 46, 1; 87-92
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Parameter calibration for the discrete element simulation model of commercial organic fertilizer
Autorzy:
Xie, C.
Yang, J.
Wang, B.
Zhuo, P.
Li, C.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/2082983.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
commercial organic fertilizer
discrete element
repose angle
parameter calibration
parameters for the particle
model
Opis:
The parameters of a discrete element simulation model for commercial organic fertilizer particles were obtained both quickly and accurately, so that the uniformity and stability of the fertilizer discharged from the feeder may be studied using the discrete element simulation method. This study screened out the parameters which significantly influenced the repose angle of the commercial organic fertilizer using the Plackett-Burman test. Then, a model for the quadratic regression response surface of the repose angle vs the parameters was established through a Box-Behnken experiment with the measured repose angle of the fertilizer particles as the optimization index. The optimization results showed that the rolling friction coefficient and static friction coefficient between the fertilizer particles, as well as the optimal simulation parameter for the Johnson-Kendall-Roberts surface energy were 0.056, 0.355 and 0.011 J m-2, respectively. A discrete element simulation test was carried out with the optimal simulation parameters, and the repose angle error of the simulation test was found to be 0.40% relative to that of the physical test, which proved the accuracy and validity of the simulation parameters for the discrete element model of the organic fertilizer. The simulation results may provide the basic parameters for establishing a discrete element model of commercial organic fertilizer particles and investigating the performance of organic fertilizer feeders using the simulation method.
Źródło:
International Agrophysics; 2021, 35, 1; 107-117
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modulation of virulence genes by the two-component system PhoP - PhoQ in avian pathogenic Escherichia coli
Autorzy:
Tu, J.
Huang, B.
Zhang, Y.
Xue, T.
Li, S.
Qi, K.
Powiązania:
https://bibliotekanauki.pl/articles/30418.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Avian pathogenic Escherichia coli (APEC) infections are a very important problem in the poultry industry. PhoP-PhoQ is a two-component system that regulates virulence genes in APEC. In this study, we constructed strains that lacked the PhoP or PhoQ genes to assess regulation of APEC pathogenicity by the PhoP-PhoQ two-component system. The PhoP mutant strain AE18, PhoQ mutant strain AE19, and PhoP/PhoQ mutant strain AE20 were constructed by the Red homologous recombination method. Swim plates were used to evaluate the motility of the APEC strains, viable bacteria counting was used to assess adhesion and invasion of chick embryo fibroblasts, and Real-Time PCR was used to measure mRNA expression of virulence genes. We first confirmed that AE18, AE19, and AE20 were successfully constructed from the wild-type AE17 strain. AE18, AE19, and AE20 showed significant decreases in motility of 70.97%, 83.87%, and 37.1%, respectively, in comparison with AE17. Moreover, in comparison with AE17, AE18, AE19, and AE20 showed significant decreases of 63.11%, 65.42%, and 30.26%, respectively, in CEF cell adhesion, and significant decreases of 59.83%, 57.82%, and 37.90%, respectively, in CEF cell invasion. In comparison with AE17, transcript levels of sodA, polA, and iss were significantly decreased in AE18, while transcript levels of fimC and iss were significantly decreased in AE19. Our results demonstrate that deletion of PhoP or PhoQ inhibits invasion and adhesion of APEC to CEF cells and significantly reduces APEC virulence by regulating transcription of virulence genes.
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 1
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation and Characterization of Ultrafine HMX/TATB Explosive Co-crystals
Autorzy:
An, C.
Li, H.
Zhang, Y.
Ye, B.
Xu, C.
Wang, J.
Powiązania:
https://bibliotekanauki.pl/articles/358105.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
HMX
TATB
ultrafine co-crystals
ball milling
mechanical sensitivity
Opis:
An explosive co-crystal of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) was prepared by the ball milling method. The raw materials and co-crystals were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Raman spectroscopy. Impact and friction sensitivity of the co-crystals were tested and analyzed. The results showed that the HMX/TATB co-crystals are spherical in shape and 100-300 nm in size. The co-crystals are different from anintimate mixture of HMX/TATB and they exhibit a new co-crystal structure. HMX/TATB co-crystals are formed by N-O···H hydrogen bonding between −NO2 (HMX) and −NH2 (TATB). The drop height of ultrafine HMX/TATB explosive co-crystals is 12.7 cm higher than that of ultrafine HMX, whilst the explosion probability of friction is 20% lower than that of ultrafine HMX. Ultrafine HMX/TATB explosive co-crystals are difficult to initiate under impact and friction conditions.
Źródło:
Central European Journal of Energetic Materials; 2017, 14, 4; 876-887
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nondestructive Evaluation of Rubber Composites Using Terahertz Time Domain Spectroscopy
Niedestrukcyjna metoda oceny kompozytów kauczukowych przy użyciu spektroskopii z wykorzystaniem technologii wykrywania terahercowego
Autorzy:
Xu, F.
Duan Mu, Q. D.
Li, L. J.
Yang, D.
Xia, B.
Powiązania:
https://bibliotekanauki.pl/articles/232361.pdf
Data publikacji:
2018
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
terahertz imaging
rubber composites
nondestructive testing
defects
wykrywanie terahercowe
materiały gumowe
badania nieniszczące
defect gumy
Opis:
In recent years, with the progress of science, more and more detection methods are being used in various fields. However, the nondestructive testing of nonmetallic materials still needs further study. In this paper, an analysis of the time domain characteristics of rubber materials using terahertz detection technology was carried out, obtaining different defect rubber material spectral characteristics as well as imaging results and data. The results show that the THz spectrum imaging technique can detect the thickness of rubber material in the 0.1 ~ 4.0 terahertz band, and the image is clear and the resolution high. Meanwhile the time domain waveform obtained is sensitive to the debonding defects of the sample rubber, is suitable for judging the overall performance of the rubber inner defect detection, and can provide the scientific basis for rubber material performance.
W artykule przedstawiono analizę charakterystyk materiałów gumowych z wykorzystaniem technologii wykrywania terahercowego, uzyskując różne charakterystyki spektralne defektów gumy, a także wyniki i dane obrazowe. Wyniki pokazały, że technika obrazowania widma THz może wykrywać grubość materiału gumowego w paśmie 0,1 ~ 4,0 terahercowym, a obraz jest wyraźny i ma wysoka rozdzielczość. W międzyczasie otrzymany przebieg domeny czasu jest wrażliwy na defekty badanej gumy, jest odpowiedni do oceny ogólnej wydajności wykrywania wewnętrznego defektu gumy i może zapewnić podstawy dla oceny właściwości materiału gumowego.
Źródło:
Fibres & Textiles in Eastern Europe; 2018, 1 (127); 67-72
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evaluation of sodium petroleum sulfonates with different molecular weights for flotation of kyanite ore
Autorzy:
Chen, B. Z.
Gao, H.
Li, Y.
Jin, J.
Ren, Z.
Wang, W.
Powiązania:
https://bibliotekanauki.pl/articles/109492.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
evaluation
sodium petroleum sulfonate
kyanite
flotation kinetics
entrainment
Opis:
The flotation performance of sodium petroleum sulfonates with different molecular weights was evaluated for flotation of a kyanite ore, by investigating valuable mineral recovery-grade, flotation kinetics and gangue entrainment. The results indicated that the higher molecular weight of agent, the higher final cumulative kyanite recovery was, with the maximum value of 72% being obtained with KY-3 with the molecular weight of 438. The final cumulative kyanite grade initially increased, and then decreased with the molecular weight increasing. In other words, the maximum final cumulative kyanite grade (i.e. 89.05%) was obtained with KY-2 with the molecular weight of 392. The kyanite flotation kinetics followed the first order kinetics well, while the modified flotation rate constant showed a decreasing trend after the initial increase as the molecular weight increased. In addition, the overall entrainment degree decreased with decreasing molecular weight of sodium petroleum sulfonates. The use of KY-2 in kyanite flotation was an attractive option in comparison with KY-1 and KY-3.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 956-968
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantum Chemical Study of Aminonitrocyclopentanes as Possible High Energy Density Materials (HEDMs)
Autorzy:
Bai, J.
Chi, W. J.
Li, L. L.
Yan, T.
Wen, X. E.
Li, B. T.
Wu, H. S.
Ma, F. L.
Powiązania:
https://bibliotekanauki.pl/articles/358101.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
cyclopentane derivatives
high energy density materials
impact sensitivity
quantum chemistry
DFT
available free space
Opis:
Nitro and amine groups were introduced into the cyclopentane skeleton, and the heats of formation, detonation performance, bond dissociation energies, and impact sensitivity for these aminonitrocyclopentanes were calculated in detail at the B3LYP/6-311G** level. The results show that all of the derivatives have negative heats of formation, which are influenced by the position of the substituent groups. Their stabilities were estimated and analyzed according to their bond dissociation energies and calculated characteristic H50 values. Most of the compounds were found to have a lower impact sensitivity than HMX. Furthermore, the detonation velocities and detonation pressures were predicted via the Kamlet-Jacobs equation. Of all these aminonitrocyclopentanes, E has the best detonation properties (ρ = 2.05 g/cm3, D = 9.11 m/s, P = 39.62 GPa) and can be considered as a candidate high energy density material.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 4; 467-480
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxygen-containing Tetrazole Salts of 3-Hydrazino-4-amino-1,2,4-triazole (HATr): Nitrogen-rich Ionic Materials with High Thermal Stability
Autorzy:
Wu, J.-T.
Zhang, J.-G.
Yin, X.
Li, T.
Wu, L.
Zhang, Z.-B.
Powiązania:
https://bibliotekanauki.pl/articles/358927.pdf
Data publikacji:
2017
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
energetic salts
thermal stability
oxygen-containing tetrazoles
3-hydrazino-4-amino-1,2,4-triazole
Opis:
Energetic salts of doubly-protonated 3-hydrazino-4-amino-1,2,4-triazole (2-4), and mono-protonated 3-hydrazino-4-amino-1,2,4-triazole (5-7), have been prepared in high yields from the corresponding oxygen-containing tetrazoles by (i) reaction of free acids and neutral 3-hydrazino-4-amino-1,2,4-triazole, or (ii) metathesis reactions of 3-hydrazinium-4-amino-1H-1,2,4-triazolium di-chloride with the silver salts of the corresponding oxygen-containing tetrazoles. All of these energetic salts were fully characterized by single-crystal X-ray diffraction, FT-IR and DSC measurements. All of the structures are dominated by extensive hydrogen bonds due to amino groups, hydrazino groups and oxygen atoms in the molecules. These salts exhibit good thermal stability, especially the salt 3-hydrazinium-4-amino-1H-1,2,4-triazolium 1H,1’H-5,5’-bitetrazole-1,1’-diolate (4), which exhibits a measured onset of decomposition temperature of 237 °C. Quantum chemical calculations, carried out using the Gaussian 03 suite of programs and based on the experimental densities were used to calculate the detonation pressures and velocities of all of the salts.
Źródło:
Central European Journal of Energetic Materials; 2017, 14, 1; 217-232
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł

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