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Wyszukujesz frazę "Liu, Qi" wg kryterium: Autor


Tytuł:
Self-catalysed hydrogenation of heavy oil and coal mixtures
Autorzy:
Li, Suan
Sun, Zhenguang
Liu, Qi
Ye, Hang
Wang, Kunpeng
Powiązania:
https://bibliotekanauki.pl/articles/27315628.pdf
Data publikacji:
2023
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
self-catalysed
heavy oil
hydrogenation
coal liquefaction
co-processing technology
Opis:
Coal liquefaction and heavy oil processing have become the urgent need for national energy strategic technology reserves in China. However, the inactivation of solid catalysts in these processes is an inevitable problem. Therefore,a self-catalysed method was proposed. The properties of raw oil could be changed by adding a modifier, as it has the function of self-catalysis, and the additional catalyst is no longer needed. The effect of 200 ppm modifier onthe hydrogenation of heavy oil and 500 ppm on the hydrogenation of coal and oil were investigated. The results showed that modifiers could be miscible with heavy oil at 50~100 °C and could change the properties of oil. When the temperature exceeded 250 °C, the sulfur element in the heavy oil combined with the metal element broughtin by the modifier to form a particle with the size of 2–8 nm, which could interact with the hydrogen molecule toactivate the hydrogen molecule. Activated hydrogen atoms further formed the complexes with nickel, vanadium,calcium, iron, and other elements in heavy oil to achieve the purpose of purifying and lightening the oil phase.Therefore, the self-catalysed method could be widely used in oil re fining and would greatly promote the development of the oil refining and catalysis industry.
Źródło:
Polish Journal of Chemical Technology; 2023, 25, 2; 8--14
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of the co-processing technology of crude oil and coal and its deployment
Autorzy:
Li, Suan
Liu, Qi
Deng, Qingyu
Ye, Hang
Zhou, Xuejie
Qiao, Aijun
Powiązania:
https://bibliotekanauki.pl/articles/2174828.pdf
Data publikacji:
2022
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
crude oil
coal
the co-processing technology
process development
industrial application
Opis:
The effect of process conditions on the co-processing technology of crude oil and coal was investigated. Crude oil/coal matching performance, swelling degree, crude oil/coal slurry viscosity-temperature characteristics and process parameters were obtained via the laboratory scale and pilot scale studies. The optimum reaction temperature of the co-processing was 445~450 °C, the pressure was 19 MPa, the catalyst addition was 3 wt.%, the reaction time was 2 h, and the ratio of hydrogen to crude oil was 1500 (V/V). Furthermore, the co-processing technology including catalyst and corresponding equipment based on the slurry bed hydrogenation were developed. By using this co-processing technology, the feed ratio of crude oil and coal can be 1:1, the coal conversion rate can be over 99%, the light oil (oil and aromatics) yield was over 70%, and the end products were gasoline, diesel, jet fuel, aromatics and LPG. The product quality meets the Euro V standard, whilst aromatics accounted for 48% of the light oil. So it was proved to be feasible to co-refine crude oil and coal at a ratio of 1:1. What’s more, the slurry bed hydrogenation plant and its equipment were tested for long-term operation, and it has been proved that this co-processing technology could be deployed as large-scale industrial application.
Źródło:
Polish Journal of Chemical Technology; 2022, 24, 4; 39--50
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of montmorillonite hydration and delamination on coal flotation
Autorzy:
Zhang, Lucheng
Zhang, Mingqing
Liu, Qi
Song, Shuoshuo
Tian, Yu
Barvora, Joshua Bosco
Powiązania:
https://bibliotekanauki.pl/articles/2175432.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
coal flotation
montmorillonite
hydration
delamination
slime coating
Opis:
In this study, the influence of montmorillonite (MT) hydration and delamination on coal flotation was investigated through flotation tests using coal-MT mixtures. MT particles were subjected to hydration at different time intervals. The Fuerstenau upgrading curve was plotted to evaluate the change in overall flotation selectivity. The zeta potential and particle size distribution were used to characterize the delamination behavior of MT in deionized water at natural pH level. Atomic force microscopy (AFM) (colloidal probe) was used to analyze the interaction force between coal and MT particles. It was found that smaller particles (individual silicate layers or thin packets of layers) with higher zeta potentials appeared gradually, and their volume proportion increased with increasing hydration time. AFM results showed that a monotonous repulsive force was detected consistently throughout the separation distance between coal and these emerging smaller MT particles. The decrease of these MT coating on coal surface was responsible for the higher flotation recovery and better selectivity. A jump-into-contact phenomenon was observed in coal and MT interaction when MT hydrated incompletely. It showed that heterocoagulation between coal and MT occurred and MT coating on the coal surface was responsible for the depression of flotation.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 6; art. no. 153085
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of a Compton backscattering wall defects detection device using the Monte Carlo method
Autorzy:
Qin, Xuan
Yang, Jianbo
Du, Zhengcong
Xu, Jie
Li, Rui
Li, Hui
Liu, Qi
Powiązania:
https://bibliotekanauki.pl/articles/24202748.pdf
Data publikacji:
2023
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
compton backscattering
Monte Carlo
nondestructive testing
wall defect
Opis:
In view of the shortcomings of traditional wall defect detection methods, such as small detection range, poor accuracy, non-portable device, and so on, a wall defects detection device based on Compton backscattering technology is designed by Monte Carlo method, which is mainly used to detect the size and location information of defects in concrete walls. It mainly consists of two parts, the source container and the detection system: first, through the simulation and analysis of the parameters such as the receiving angle of thebackscattered particles and the rear collimating material of the detector, the influence of the fluorescent X-ray peak of the detector collimating material on the backscattered particle counts is eliminated and the detected error is reduced; second, the ring array detector design, compared with single array detector and surface array detector, can facilitate real-time detection of defect orientation, expanding the single scan range and improving the detection efficiency. After simulation and comparative analysis, the relevant optimal parameters are obtained: the object is detected using a Cs-137 γ-ray source with an activity of 6 mCi, and a ring detector consisting of four 0.5-inch cube-shaped CsI scintillator detectors is placed at 150° to receive the backscattered photons. The simulation analysis using the Monte Carlo FLUKA program showed that the maximum depth of wall defect detection is 8 cm, the maximum error fl uctuation range of defect depth and thickness is ±1 cm, the overall device weight is <20 kg, and the measurement time is <5 min.
Źródło:
Nukleonika; 2023, 68, 2; 57--63
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption of lanthanum(III) and yttrium(III) on kaolinite: kinetics and adsorption isotherms
Autorzy:
Zhou, Fang
Feng, Jian
Xie, Xiong
Wu, Baihong
Liu, Qi
Wu, Xiaoyan
Chi, Ruan
Powiązania:
https://bibliotekanauki.pl/articles/109951.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
adsorption
kaolinite
rare earth
kinetics
Opis:
Experimental investigations were carried out using kaolinite to adsorb two rare earth ions, lanthanum ion (La3+) and yttrium ion (Y3+), which will provide some useful information and new insights on the mineralization process and fractionation phenomenon of weathered crust elution-deposited rare earth ores. The results showed that the equilibrium adsorption capacity of Y3+ is greater than La3+ under the same experimental conditions. The adsorption of rare earth ions presents strongly temperature dependent indicating an endothermic adsorption process. The pseudo-first-order kinetic model and the pseudo-second-order kinetic model were applied to discuss the adsorption kinetics. It was found that the adsorption rate of rare earth follows the pseudo-second-order kinetic model among the adsorption temperature range. Furthermore, the adsorption process of rare earth ions on kaolinite followed the Langmuir isotherm model confirmed by the correlation of experimental equilibrium data to standard isotherm model, Langmuir and Freundlich isotherms. The activation energies for the adsorption of La3+ and Y3+ on kaolinite are 28.1903 kJ/mol and 25.4190 kJ/mol, respectively. All kaolinite before and after adsorption were characterized by XRD and SEM-EDX to understand the adsorption mechanism. The obtained results suggested that the adsorption of La3+ and Y3+ on kaolinite is an endothermic and chemisorption process.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 4; 928-939
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Looped-chain-based active current sharing strategy in DC microgrids
Autorzy:
Li, D.
Liu, Y.
Gu, Y.
Qi, H.
Powiązania:
https://bibliotekanauki.pl/articles/141109.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
active current sharing
DC microgrids
looped control diagram
Opis:
The integration of renewable energy sources in modern electric grids have drawn increasing attention nowadays. In order to effectively manage large-scale renewable energy sources and achieve flexible and efficient operation, the concept of microgrids have been proposed. Considering the nature of DC outputs in many distributed energy resources (DERs), DC microgrids have been extensively studied in the past years. Among the operational issues in DC microgrids, current sharing issues have become an important topic since it is highly relevant to the operation of DC microgrids. By adopting a proper design of current sharing strategy in DC microgrids, the current rating violations in each interface converter can be successfully avoided. In this paper, a looped-chainbased active current sharing strategy is proposed to realize high accuracy current sharing in DC microgrids. In particular, the output current is shared between the neighboring interface converters. Hence, following a clockwise or counter-clockwise order, a loopedchain- based control diagram can be established to share the reference value of the output current. A final status in the whole DC microgrid is that the output current of every interface converter is equalized. Hence, the desired current sharing objective can be satisfied. A MATLAB simulation model is established to verify the proposed loopedchain- based active current sharing strategy in DC microgrids.
Źródło:
Archives of Electrical Engineering; 2017, 66, 3; 559-569
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Laser Welding of TA15 Titanium Alloy and Inconel 718 Dissimilar Metals
Autorzy:
An, Qi
Wu, Dongting
Liu, Peng
Zou, Yong
Powiązania:
https://bibliotekanauki.pl/articles/2174556.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
TA15 titanium alloy
Inconel 718 nickel-based alloy
laser welding
microstructure
tensile strength and fracture characteristic
Opis:
This paper studied the effect of laser welding technology on dissimilar metal welding joints of TA15 titanium alloy and Inconel 718 nickel-based alloy. The research results indicate that the laser welding of TA15 titanium alloy and Inconel 718 nickel-based alloy directly was difficult to form well, which due to the intermetallic compounds caused the joint brittle. When the pure Cu foil was used as the filling layer, the quality of the welding joints can be improved effectively. The experimental results also indicate that there were brittle intermetallic-compounds in the laser welding seam, and the laser power had an important influence on the performance and mechanical properties of the dissimilar metal joint. The maximum average tensile strength of the welding joint of 2300 W was increased to 252.32 MPa. Scanning electron microscope(SEM) results show that the fracture morphology was river pattern, a typical morphological of cleavage fracture, and the mode was brittle fracture.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 4; 1267--1276
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The presence of Chlamydia phage PhiCPG1 capsid protein VP1 genes and antibodies in patients infected with Chlamydia trachomatis
Autorzy:
Ma, Jingyue
Liu, Yuan
Liu, Yuanjun
Li, Lingjie
Hou, Shuping
Gao, Xibo
Qi, Manli
Liu, Quanzhong
Powiązania:
https://bibliotekanauki.pl/articles/1038770.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Chlamydia trachomatis
Chlamydia bacteriophage
capsid protein
VP1
Opis:
Chlamydia phage PhiCPG1 has been found in Chlamydia caviae in a guinea pig model for inclusion conjunctivitis, raising the possibility that Chlamydia phage is also present in patients infected with C. trachomatis (Ct). In the present study, we assayed for presence of Chlamydia phage capsid protein VP1 genes and antibodies in 84 non-Ct controls and 206 Ct patients using an enzyme-linked immunoassay (ELISA), followed by verification with Western blot. None of the subjects were exposed to an antibiotic treatment or had a C. pneumoniae infection. The VP1 antibody test was positive in both, the ELISA and Western blot assay, in 4 Ct patients. PCR amplification experiments revealed presence of the VP1 gene in 5 Ct patients. The results suggest that Chlamydia phage capsid protein VP1 may exist in some Ct patients.
Źródło:
Acta Biochimica Polonica; 2016, 63, 3; 501-504
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Metal Oxides on the Thermal Decomposition Kinetics and Mechanisms of HAN/PVA Based Propellants
Autorzy:
Hu, Song-qi
Liu, Xue-li
Liu, Lin-Lin
Kang, Bo
Zhang, Yan
Powiązania:
https://bibliotekanauki.pl/articles/27787991.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
HAN/PVA-based propellant
metal oxides
catalytic behaviour
kinetic parameters
Opis:
The thermal decomposition processes of HAN/PVA-based propellants have been investigated using a simultaneous thermogravimetric analysis (TGA) – differential scanning calorimetry (DSC), coupled with Fourier-Transform Infrared Spectroscopy (FTIR) and Mass Spectrometry (MS) system. The activation energy (Ea), pre-exponential factor A and reaction mechanism function f(α) of the decomposition processes have been determined by non-isothermal and Malek methods. The results showed that the decomposition process of an HAN/PVA sample occurs mainly in the temperature range 202.2~220.1 °C, with a mass loss, heat release and Ea of about 84.8%, 1474.18 and 88.76 kJ·mol–1, respectively. Of the seven metal oxides studied as catalysts, Al2O3, V2O5 and Fe2O3 have significant catalytic effects on an HAN/PVA-based propellant, in lowering the decomposition temperature, with Ea changing from 88.8 to 83.7, 85.6 and 113.6 kJ·mol–1, respectively. The f(α) of both HAN/PVA and HAN/PVA/Al2O3 samples can be expressed as f(α) = (1 – α)2, whereas f(α) = α or f(α) = α/2 fit well for the HAN/PVA/V2O5 and HAN/PVA/Fe2O3 samples.
Źródło:
Central European Journal of Energetic Materials; 2021, 18, 3; 322-338
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on Friction and Wear Characteristics of Aluminum Alloy Hydraulic Valve Body and Its Antiwear Mechanism
Autorzy:
Rong, L.
Lunjun, Ch.
Ming, Su
Qi, Z.
Yong, Liu
Powiązania:
https://bibliotekanauki.pl/articles/382468.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
aluminum alloy
hydraulic valve body
oil leakage
friction and wear
stop aluminium
korpus zaworu hydraulicznego
wycieki oleju
tarcie i zużycie
Opis:
In order for the working status of the aluminum alloyed hydraulic valve body to be controlled in actual conditions, a new friction and wear design device was designed for the cast iron and aluminum alloyed valve bodies comparison under the same conditions. The results displayed that: (1) The oil leakage of the aluminum alloyed hydraulic valve body was higher than the corresponding oil leakage of the iron body during the initial running stage. Besides during a later running stage, the oil leakage of the aluminum alloyed body was lower than corresponding oil leakage of the iron body; (2) The actual oil leakage of different materials consisted of two parts: the foundation leakage that was the leakage of the valve without wear and wear leakage that was caused by the worn valve body; (3) The aluminum alloyed valve could rely on the dust filling furrow and melting mechanism that led the body surface to retain dynamic balance, resulting in the valve leakage preservation at a low level. The aluminum alloy modified valve body can meet the requirements of hydraulic leakage under pressure, possibly constituting this alloy suitable for hydraulic valve body manufacturing.
Źródło:
Archives of Foundry Engineering; 2017, 17, 1; 207-215
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mixed leaf litter decomposition and N, P release with a focus on Phyllostachys edulis (Carriere) J. Houz. forest in subtropical southeastern China
Autorzy:
Shi, L.
Fan, S.
Jiang, Z.
Qi, L.
Liu, G.
Powiązania:
https://bibliotekanauki.pl/articles/56692.pdf
Data publikacji:
2015
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
leaf litter
decomposition
nitrogen
phosphorus
Phyllostachys edulis
moso bamboo
tortoise-shell bamboo zob.moso bamboo
forest
subtropical area
China
Opis:
As an important non-wood forest product and wood substitute, Moso bamboo grows extremely rapidly and hence acquires large quantities of nutrients from the soil. With regard to litter decomposition, N and P release in Moso bamboo forests is undoubtedly important; however, to date, no comprehensive analysis has been conducted. Here, we chose two dominant species (i.e., Cunninghamia lanceolata and Phoebe bournei), in addition to Moso bamboo, which are widely distributed in subtropical southeastern China, and created five leaf litter mixtures (PE100, PE80PB20, PE80CL20, PE50PB50 and PE50CL50) to investigate species effects on leaf litter decomposition and nutrient release (N and P) via the litterbag method. Over a one-year incubation experiment, mass loss varied significantly with litter type (P < 0.05). The litter mixtures containing the higher proportions (>80%) of Moso bamboo decomposed faster; the remaining litter compositions followed Olson's decay mode well (R2 > 0.94, P < 0.001). N and P had different patterns of release; overall, N showed great temporal variation, while P was released from the litter continually. The mixture of Moso bamboo and Phoebe bournei (PE80PB20 and PE50PB50) showed significantly faster P release compared to the other three types, but there was no significant difference in N release. Litter decomposition and P release were related to initial litter C/N ratio, C/P ratio, and/or C content, while no significant relationship between N release and initial stoichiometric ratios was found. The Moso bamboo-Phoebe bournei (i.e., bamboo-broadleaved) mixture appeared to be the best choice for nutrient return and thus productivity and maintenance of Moso bamboo in this region.
Źródło:
Acta Societatis Botanicorum Poloniae; 2015, 84, 2
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Intelligent fault diagnosis of rolling bearings based on continuous wavelet transform-multiscale feature fusion and improved channel attention mechanism
Autorzy:
Zhang, Jiqiang
Kong, Xiangwei
Cheng, Liu
Qi, Haochen
Yu, Mingzhu
Powiązania:
https://bibliotekanauki.pl/articles/24200817.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
deep learning
continuous wavelet transform
improved channel attention mechanism
multi-conditions
convolutional neural network
Opis:
Accurate fault diagnosis is critical to operating rotating machinery safely and efficiently. Traditional fault information description methods rely on experts to extract statistical features, which inevitably leads to the problem of information loss. As a result, this paper proposes an intelligent fault diagnosis of rolling bearings based on a continuous wavelet transform(CWT)-multiscale feature fusion and an improved channel attention mechanism. Different from traditional CNNs, CWT can convert the 1-D signals into 2-D images, and extract the wavelet power spectrum, which is conducive to model recognition. In this case, the multiscale feature fusion was implemented by the parallel 2-D convolutional neural networks to accomplish deeper feature fusion. Meanwhile, the channel attention mechanism is improved by converting from compressed to extended ways in the excitation block to better obtain the evaluation score of the channel. The proposed model has been validated using two bearing datasets, and the results show that it has excellent accuracy compared to existing methods.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 1; art. no. 16
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Estimation of wind erosion rates of Mongolian Plateau by using 137Cs tracing technique
Ocena intensywnosci erozji eolicznej Plaskowyzu Mongolskiego z wykorzystaniem techniki oznaczania 137Cs
Autorzy:
Qi, Y
Liu, J.
Shi, H.
Zhuang, D.
Hu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/81677.pdf
Data publikacji:
2010
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
estimation
wind erosion
erosion rate
Mongolian Plateau
137Cs tracing technique
Opis:
Wind erosion is one of the major environmental problems in semi-arid and arid regions. Here we established a transect from northwest (Tariat, Mongolia) to southeast (Xilingol, Inner Mongolia of China) across the Mongolian Plateau, and selected eight sampling sites along the transect. We then estimated the soil wind erosion rates by using the 137Cs tracing technique and examined their spatial dynamics. In the Mongolia section (from Tariat to Sainshand), the wind erosion rate increased gradually with vegetation type and climatic regimes; the wind erosion process was controlled by physical factors such as annual precipitation and vegetation coverage, etc. While in the China section (Inner Mongolia), the wind erosion rates of Xilinhot, Zhengxiangbai Banner and Taipusi Banner were thrice as much as those of Bayannur of Mongolia, although these four sites were all dominated by typical steppe. Besides the physical factors, higher population density and livestock carrying level should be responsible for the higher wind erosion rates in these regions of Inner Mongolia.
W pracy przedstawiono wyniki badań intensywności erozji eolicznej Płaskowyżu Mongolskiego, określonej na podstawie ośmiu prób gruntu pobranego wzdłuż transektu o długości około 1400 km, przebiegającego przez teren Mongolii i Chin. Do oceny intensywności erozji wykorzystano technikę oznaczania 137Cs w wierzchnich warstwach gruntu do głębokości 30 cm. Stwierdzono, że intensywność erozji w analizowanym transekcie od północnego-zachodu stopniowo wzrasta wraz ze zmianami reżimu klimatycznego (zmniejszania się rocznej wysokości opadów), a także zmianami pokrycia roślinnego. Chińska część Płaskowyżu o charakterze stepowym jest trzykrotnie bardziej intensywnie erodowana. Oprócz czynników fizycznych, na intensywność procesu erozji eolicznej wpływa większa gęstość zaludnienia Płaskowyżu na terenie Chin, a także większe pogłowie zwierząt hodowlanych.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation; 2010, 42, 1; 197-208
0208-5771
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chlamydial genomic MinD protein does not regulate plasmid-dependent genes like Pgp5
Autorzy:
Sun, Yina
Kong, Jie
Ma, Jingyue
Qi, Manli
Zhang, Ying
Han, Long
Liu, Quanzhong
Liu, Yuanjun
Powiązania:
https://bibliotekanauki.pl/articles/1038373.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
Chlamydia
MinD
Pgp5
Transformation system
Opis:
Chlamydia has a unique intracellular developmental cycle, which has hindered the single protein function study of Chlamydia. Recently developed transformation system of Chlamydia has greatly advanced the chlamydial protein's function research and was used to find that a chlamydial plasmid-encoded Pgp5 protein can down-regulate plasmid-dependent genes. It is assumed, that chlamydial genomic MinD protein has a similar function to Pgp5. However, it is unknown whether MinD protein regulates the same plasmid-dependent genes. We replaced pgp5 gene in the shuttle vector pGFP::CM with minD gene of C. trachomatis (CT0582) or C. muridarum (TC0871). The recombinant plasmid was transformed into plasmid-free organisms-CMUT3 and qRT-PCR was used to detect the transcription level of plasmid-encoded and -dependent genes in these pgp5 deficient organisms. As a readout, GlgA, one of the plasmid-regulated gene products was detected by immunofluorescence assay. After recombination, transformation and plaque purification, the stable transformants CT0582R and TC0871R were generated. In these transformants, the plasmid-dependent genes were up-regulated, alike in the pgp5 premature stop mutant and pgp5 replacement with mCherry mutant. GlgA protein level was also increased in all pgp5 mutants, including CT0582R and TC0871R. Thus, our study showed that genomic MinD protein had different function than Pgp5, which was useful for further understanding the chlamydiae.
Źródło:
Acta Biochimica Polonica; 2018, 65, 3; 425-429
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
In vitro co-stimulation of anti-tumor activity by soluble B7 molecules
Autorzy:
He, Wei
Hu, Zhong-Bo
Liu, Fang
Feng, Xian-Qi
Zou, Ping
Powiązania:
https://bibliotekanauki.pl/articles/1041178.pdf
Data publikacji:
2006
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
immunotherapy
tumor escape
gene fusion
recombinant fusion proteins
Opis:
In order to investigate the anti-tumor activity of a soluble B7-1/immunoglobulin G fusion protein and explore an effective method to eliminate immune escape of tumor cells, a recombinant vector encoding this fusion protein was constructed and constitutively expressed in Chinese hamster ovary cells. After purification with protein G affinity chromatography, the soluble fusion protein was tested for bioactivity. Results showed that the fusion protein could significantly increase the density of B7-1 molecules on WEHI-3 cells, a mouse leukemia cell line. Through allogeneic mixed lymphocyte tumor cultures, it was demonstrated that, with the presence of the first signal, it could also significantly enhance T cell activation and killing activity against WEHI-3 cells and interleukin-2 secretion by activated mouse T lymphocytes. The conclusion can be drawn that the soluble B7-IgG fusion protein has a potent capacity to generate or enhance anti-tumor immune response in vitro, and its clinical value deserves further investigation.
Źródło:
Acta Biochimica Polonica; 2006, 53, 4; 807-813
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Infrared small-target detection under a complex background based on a local gradient contrast method
Autorzy:
Yang, Linna
Xie, Tao
Liu, Mingxing
Zhang, Mingjiang
Qi, Shuaihui
Yang, Jungang
Powiązania:
https://bibliotekanauki.pl/articles/2201024.pdf
Data publikacji:
2023
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
small target detection
local gradient contrast
visual saliency
infrared image processing
kontrast lokalny
wyróżnienie wizualne
obrazowanie w podczerwieni
Opis:
Small target detection under a complex background has always been a hot and difficult problem in the field of image processing. Due to the factors such as a complex background and a low signal-to-noise ratio, the existing methods cannot robustly detect targets submerged in strong clutter and noise. In this paper, a local gradient contrast method (LGCM) is proposed. Firstly, the optimal scale for each pixel is obtained by calculating a multiscale salient map. Then, a subblockbased local gradient measure is designed; it can suppress strong clutter interference and pixel-sized noise simultaneously. Thirdly, the subblock-based local gradient measure and the salient map are utilized to construct the LGCM. Finally, an adaptive threshold is employed to extract the final detection result. Experimental results on six datasets demonstrate that the proposed method can discard clutters and yield superior results compared with state-of-the-art methods.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2023, 33, 1; 33--43
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adptive heading control of underactuated unmanned surface vehicle based on improved backpropagation neural network
Autorzy:
Dong, Zaopeng
Li, Jiakang
Liu, Wei
Zhang, Haisheng
Qi, Shijie
Zhang, Zhengqi
Powiązania:
https://bibliotekanauki.pl/articles/32917278.pdf
Data publikacji:
2023
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
underactuated unmanned surface vehicle
backpropagation neural network controller
heading control
hyperbolic tangent function
Opis:
Aiming at the challenges to the accurate and stable heading control of underactuated unmanned surface vehicles arising from the nonlinear interference caused by the overlay and the interaction of multi interference, and also the uncertainties of model parameters, a heading control algorithm for an underactuated unmanned surface vehicle based on an improved backpropagation neural network is proposed. Based on applying optimization theory to realize that the underactuated unmanned surface vehicle tracks the desired yaw angle and maintains it, the improved momentum of weight is combined with an improved tracking differentiator to improve the robustness of the system and the dynamic property of the control. A hyperbolic tangent function is used to establish the nonlinear mappings an approximate method is adopted to summarize the general mathematical expressions, and the gradient descent method is applied to ensure the convergence. The simulation results show that the proposed algorithm has the advantages of strong robustness, strong anti-interference and high control accuracy. Compared with two commonly used heading control algorithms, the accuracy of the heading control in the complex environment of the proposed algorithm is improved by more than 50%.
Źródło:
Polish Maritime Research; 2023, 1; 54-64
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation Evaluation Method for Fusion Characteristics of the Optical Camouflage Pattern
Metoda oceny symulacji charakterystyk wzoru kamuflażu optycznego
Autorzy:
Yang, Xin
Xu, Wei-Dong
Liu, Jun
Jia, Qi
Zhu, Wan-Nian
Powiązania:
https://bibliotekanauki.pl/articles/1419455.pdf
Data publikacji:
2021
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
camouflage pattern evaluation
effect evaluation
sampling statistics
visual feature
kamuflaż
efekt oddziaływania
próbkowanie
funkcja wizualna
Opis:
A comprehensive evaluation system for a camouflage design combining local effect evaluation and global sampling is developed. Different from previous models, this method can sample and evaluate target camouflage in a wide range of combat areas, thereby obtaining a comprehensive evaluation effect. In evaluating local effects, the Gaussian pyramid model is adopted to decompose the image on a multi-scale so that it can conform to the multi-resolution property of human eyes. The Universal Image Quality Index (UIQI) conforming to features of eye movements is then adopted to measure the similarities between multi-scale targeted and background brightness, color and textural features. In terms of the imitation camouflage pattern design algorithm, uniform sampling is used to obtain the evaluation distribution in the background; while for the deformation camouflage pattern, the sampling distribution is improved to make it conform to the movement rule of the target in the background. The evaluation results of the model for different designs were investigated. It is suggested by the experimental results that the model can compare and evaluate the indicators involved in the process of camouflage design, including integration, polychromatic adaptability and algorithm stability. This method can be applied in the evaluation and contrast of camouflage pattern design algorithms, in parameter optimisation of camouflage design and in scheme comparison in engineering practice, and can provide support of evaluation methodology for camouflage design theories.
W pracy opracowano kompleksowy system oceny projektu kamuflażu, łączący ocenę efektu lokalnego i próbkowanie globalne. W odróżnieniu od poprzednich modeli, ta metoda może próbkować i oceniać kamuflaż celu w szerokim zakresie obszarów walki, uzyskując w ten sposób kompleksowy efekt oceny. Oceniając efekty lokalne, przyjęto model piramidy Gaussa w celu dekompozycji obrazu w wielu skalach, tak aby mógł on być zgodny z właściwościami i rozdzielczością ludzkiego oka. Następnie przyjęto uniwersalny wskaźnik jakości obrazu (UIQI) zgodny z cechami ruchów oczu, tak aby zmierzyć podobieństwa między celowaniem w wielu skalach a jasnością tła, kolorem i cechami tekstury. Jeśli chodzi o algorytm projektowania imitacji wzoru kamuflażu, w celu uzyskania rozkładu oceny w tle zastosowano jednolite próbkowanie; podczas gdy w przypadku wzoru kamuflażu deformacji poprawiono rozkład próbkowania, tak aby był zgodny z regułą ruchu celu w tle. Zbadano wyniki oceny modelu dla różnych projektów. Wyniki eksperymentów wykazały, że model może służyć do porównania i oceny wskaźników procesu projektowania kamuflażu, w tym integrację, polichromatyczną adaptowalność i stabilność algorytmu. Metoda przedstawiona w pracy może znaleźć zastosowanie w ocenie algorytmów projektowania wzorów kamuflażu, w optymalizacji parametrów projektowania kamuflażu i przy porównywaniu schematów w praktyce inżynierskiej, a także może stanowić wsparcie dla metodologii oceny teorii projektowania kamuflażu.
Źródło:
Fibres & Textiles in Eastern Europe; 2021, 3 (147); 103-110
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
SCREENING THE SPECIFIC SUBSTRATES OF ADENYLATION DOMAIN FROM MARINE ACTINOMYCETES BY FLUORESCENCE QUENCHING AND ISOTHERMAL TITRATION CALORIMETRY
Autorzy:
LEI, MING
ZHAO, ZHIJUAN
LIU, KE
LIU, YANLI
ZHANG, HUI
WU, XUE
GONG, SIYING
MA, YANLING
ZHAO, HAOBIN
LIU, JINLIN
MIN, JINRONG
QI, CHAO
Powiązania:
https://bibliotekanauki.pl/articles/895432.pdf
Data publikacji:
2018-12-31
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Tematy:
A domain
Aspartic acid
Fluorescence quenching (FQ)
Isothermal titration calorimetry (ITC)
Marine actinomycetes
static quenching
Opis:
Adenylation domain (A domain) is a model of non-ribosomal peptide synthetases (NRPs), responsible for binding and activating the substrates-amino acids. In this study, a pGEX-2T-sare0718 recombinant plasmid (the gene sare0718 was cloned from Salinispora arenicola CNS-205, S.arenicola CNS-205) was transformed and expressed as a protein GST-Sare0718. Fluorescence quenching (FQ) was conducted to investigate the binding of 20 common amino acids to GST-Sare0718, then isothermal titration calorimetry (ITC) also be used[changed]. The results of FQ revealed that intrinsic fluorescence of GST-Sare0718 is quenched steadily by addition of aspartic acid (Asp) and glutamine (Gln) through static quenching mechanism. The binding constants Ka are Asp (1.504×106 L/mol) ≥ Gln (1.468×105 L/mol). And there is one binding site on the protein GST-Sare0718. We confirmed Asp preference of GST-Sare0718 by ITC. Therefore, Asp is the specific substrate. In addition, the experimental data indicates that the prediction system, “the specificity-conferring code”, is not suitable for marine actinomycetes. So it is urgent to set up a special predictive system for marine actinomycetes.
Źródło:
Acta Poloniae Pharmaceutica - Drug Research; 2018, 75, 6; 1287-1292
0001-6837
2353-5288
Pojawia się w:
Acta Poloniae Pharmaceutica - Drug Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Camouflage Assessments with Digital Pattern Painting Based on the Multi-Scale Pattern-in-Picture Evaluation Model
Autorzy:
Jia, Qi
Xu, Weidong
Yi, Yang
Liu, Jun
Hu, Jianghua
Zhu, Liyan
Yang, Xin
Powiązania:
https://bibliotekanauki.pl/articles/24200962.pdf
Data publikacji:
2023
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
computer-aided
camouflage assessment
pattern painting
evaluation
simulation
military camouflage
Opis:
In general, traditional evaluations of target camouflage effects are usually conducted based on observational data and general results of statistical analysis. This widely applied methodology quantifies the detection and identification probabilities of camouflage objects but has considerable shortcomings. This data evaluation process is laborious and time-consuming and very low in reproducibility, which sheds light on the necessity of developing a more efficient method in this study field. The growth of computeraided image processing technology provides technical support for camouflage effect evaluation based on digital image processing. Digital pattern painting, which has been previously applied to combat utility uniforms, is a new methodology full of potential due to its broad geographical adaptability. This study proposes a multi-scale pattern-in-picture method to evaluate camouflage effects at different distances. We also established a computer-aided background image library and camouflage assessments with digital simulation and created an evaluation system that could be effectively applied to combat utility uniforms. More than 40 testers participated in this study, who were asked to score the designed camouflage schemes using the evaluation system proposed. The data from simulation assessments and individual evaluations show that the computer-aided simulation assessments conducted as part of this research can efficiently and objectively evaluate the camouflage effect on military objects.
Źródło:
Fibres & Textiles in Eastern Europe; 2023, 31, 2; 39--50
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Activation of quartz flotation by Cu2+, Ni2+ in the sodium ethylxanthogenate (EX) system
Autorzy:
Liu, Yang
Tong, Xiong
Xie, Rui-Qi
Xie, Xian
Song, Qiang
Fan, Pei-Qiang
Powiązania:
https://bibliotekanauki.pl/articles/24085981.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quartz
flotation
ions activation
sodium ethylxanthogenate
adsorption mechanism
Opis:
During the flotation of metal sulfide minerals, due to the interference of unavoidable ions, the quartz also partially floats in some cases. The studies on the mechanism of quartz being activated and floating up are still insufficient. In this study, the influence of the Cu2+ and Ni2+ unavoidable ions on the floatation of quartz was studied by micro-flotation experiments, adsorption detection, zeta potential measurement, solution composition calculation, infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses, and atomic force microscopy (AFM) observation. This provides a theoretical reference for further understanding the mechanism of sodium ethylxanthogenate and quartz surface, as well as the development of a new quartz depressant. The results of flotation showed that after activation by Cu2+ (1×10-4 mol/dm3) and Ni2+ (5×10-5 mol/dm3), the quartz was captured by sodium ethylxanthogenate (EX: 1.4×10-4 mol/dm3) under alkaline conditions (pH=10), while the best recoveries were obtained as 80% and 43%, respectively. The results of adsorption and zeta potential measurements showed that the precipitation rate of Cu2+ was greater than that of Ni2+ under alkaline conditions. Additionally, both Cu2+ and Ni2+ electrostatically adsorbed on the quartz surface and changed the zeta potential of quartz. The solution composition calculation further showed that Cu(OH)+, Cu(OH)2(s), and Ni(OH)+, Ni(OH)2(s) were the main components in the solution under alkaline conditions. The FT-IR and XPS analyses and AFM observations demonstrated that Cu and Ni species adsorbed on O atoms on the quartz surface, providing active sites for EX adsorption, and EX combines with Cu and Ni species on the quartz surface to generate -O-Cu-EX and -O-Ni-EX complexes. Finally, the quartz floated up due to the formation of hydrophobic products and firm adsorption.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 166368
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical study on the dynamic response of a concrete filled steel tubular long column under axial impact by a rigid-body
Autorzy:
Qi, Han
Chen, Shuohui
Zou, Jianlei
Zhang, Huidi
Liu, Mengsha
Ju, Jinsan
Sang, Xiuxing
Powiązania:
https://bibliotekanauki.pl/articles/2055059.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
concrete filled steel tubular long column
rigid body
impact load
dynamic response
Opis:
In this study, refined finite element models of concrete filled steel tubular long columns with length diameter ratio (L/D) of 50 were established, and their dynamic responses under a rigid-body impact were explored. It is found that the form of impact load is only related to and can be predicted from the impact velocity of the rigid-body. The change of axial stress and strain with time is synchronous with that of the impact load. Furthermore, the variation characteristics of axial stress and strain with time are mainly related to the initial velocity of the rigid-body.
Źródło:
Journal of Theoretical and Applied Mechanics; 2021, 59, 4; 551--563
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis, Crystal Structure, and Properties of a Novel, Highly Sensitive Energetic, Coordination Compound: Iron (II) Carbohydrazide Perchlorate
Autorzy:
Liu, R.
Zhou, Z.
Qi, S.
Yang, L.
Wu, B.
Huang, H.
Zhang, T.
Powiązania:
https://bibliotekanauki.pl/articles/358343.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
iron (II) carbohydrazide perchlorate
energetic material
high
sensitivity
DFT
energy gap
Opis:
A single crystal of iron (II) carbohydrazide perchlorate [FeII (CHZ)3](ClO4)2 (FeCP), a novel, lead-free, energetic coordination compound, was synthesized and its structure determined by X-ray single crystal diffraction for the frst time. The crystal belongs to the monoclinic system P2(1)/n space group, with a = 1.0066(2) nm, b = 0.8458(2) nm, c = 2.1194(4) nm, β = 100.693(3)° and Z = 4. The central Fe(II) ion is coordinated to three bidentate carbohydrazide units through the carbonyl oxygen atom and an amino nitrogen atom, forming a six-coordinated, non-centrosymmetric complex cation. The thermal analyses by differential scanning calorimetry and thermogravimetry show that the onset temperature of thermal decomposition (152.7 °C) and the critical temperature of thermal explosion of FeCP (161.2 °C) are both much lower than those of other transition metal carbohydrazide perchlorate compounds, and also those of some other primary explosives in service. FeCP has a high enthalpy of combustion, as measured by oxygen bomb calorimetry. The impact, friction and fame sensitivity tests indicate that FeCP is extremely sensitive and hazardous. Unexpected explosions occurred even during the operational processes. In order to explore the intrinsic cause of these explosions, theoretical calculations of the orbital energies were performed based on DTF. These results reveal that the impact sensitivity is positively correlated with the energy gap between HOMO and LUMO: the smaller energy gap results in the higher impact sensitivity.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 1; 17-36
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An improved dynamic surface sliding mode method for autonomous cooperative formation control of underactuated USVS with complex marine environment disturbances
Autorzy:
Dong, Zaopeng
Qi, Shijie
Yu, Min
Zhang, Zhengqi
Zhang, Haisheng
Li, Jiakang
Liu, Yang
Powiązania:
https://bibliotekanauki.pl/articles/32909478.pdf
Data publikacji:
2022
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
underactuated USV
dynamic surface sliding mode control
lateral velocity tracking differentiator
nonlinear disturbance observer
Opis:
In this paper, a novel dynamic surface sliding mode control (DSSMC) method, combined with a lateral velocity tracking differentiator (LVTD), is proposed for the cooperative formation control of underactuated unmanned surface vehicles (USVs) exposed to complex marine environment disturbances. Firstly, in view of the kinematic and dynamic models of USVs and the design idea of a virtual control law in a backstepping approach, the trajectory tracking control problem of USVs’ cooperative formation is transformed into a stabilisation problem of the virtual control law of longitudinal and lateral velocities. Then, aiming at the problem of differential explosion caused by repeated derivation in the process of backstepping design, the first-order low-pass filter about the virtual longitudinal velocity and intermediate state quantity of position is constructed to replace differential calculations during the design of the control law, respectively. In order to reduce the steady-state error when stabilising the virtual lateral velocity control law, the integral term is introduced into the design of the sliding mode surface with a lateral velocity error, and then the second-order sliding mode surface with an integral is structured. In addition, due to the problem of controller oscillation and the role of the tracking differentiator (TD) in active disturbance rejection control (ADRC), the LVTD is designed to smooth the state quantity of lateral velocity. Subsequently, based on the dynamic model of USV under complex marine environment disturbances, the nonlinear disturbance observer is designed to observe the disturbances and compensate the control law. Finally, the whole cooperative formation system is proved to be uniformly and ultimately bounded, according to the Lyapunov stability theory, and the stability and validity of the method is also verified by the simulation results.
Źródło:
Polish Maritime Research; 2022, 3; 47-60
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł

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