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Wyszukujesz frazę "Li, Mei" wg kryterium: Autor


Tytuł:
VMD and CNN-Based Classification Model for Infrasound Signal
Autorzy:
Lu, Quanbo
Li, Mei
Powiązania:
https://bibliotekanauki.pl/articles/31339812.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
infrasound signal
variational mode decomposition
convolutional neural network
Fast Fourier Transform
Opis:
Infrasound signal classification is vital in geological hazard monitoring systems. The traditional classification approach extracts the features and classifies the infrasound events. However, due to the manual feature extraction, its classification performance is not satisfactory. To deal with this problem, this paper presents a classification model based on variational mode decomposition (VMD) and convolutional neural network (CNN). Firstly, the infrasound signal is processed by VMD to eliminate the noise. Then fast Fourier transform (FFT) is applied to convert the reconstructed signal into a frequency domain image. Finally, a CNN model is established to automatically extract the features and classify the infrasound signals. The experimental results show that the classification accuracy of the proposed classification model is higher than the other model by nearly 5%. Therefore, the proposed approach has excellent robustness under noisy environments and huge potential in geophysical monitoring.
Źródło:
Archives of Acoustics; 2023, 48, 3; 403-412
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Infrasound Signal Classification Based on ICA and SVM
Autorzy:
Lu, Quanbo
Wang, Meng
Li, Mei
Powiązania:
https://bibliotekanauki.pl/articles/31339863.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
independent component analysis
fast Fourier transform
support vector machine
infrasound signal
Opis:
A diagnostic technique based on independent component analysis (ICA), fast Fourier transform (FFT), and support vector machine (SVM) is suggested for effectively extracting signal features in infrasound signal monitoring. Firstly, ICA is proposed to separate the source signals of mixed infrasound sources. Secondly, FFT is used to obtain the feature vectors of infrasound signals. Finally, SVM is used to classify the extracted feature vectors. The approach integrates the advantages of ICA in signal separation and FFT to extract the feature vectors. An experiment is conducted to verify the benefits of the proposed approach. The experiment results demonstrate that the classification accuracy is above 98.52% and the run time is only 2.1 seconds. Therefore, the proposed strategy is beneficial in enhancing geophysical monitoring performance.
Źródło:
Archives of Acoustics; 2023, 48, 3; 191-199
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Preparation of magnesium hydroxide by modifier-directed hydration and its effect on flame retardancy and mechanical properties of polypropylene
Autorzy:
Wang, Mei Jia
Bai, Li Mei
Zhang, Meng Ting
Ma, Yu Xin
Zhao, Liu Cheng
Li, Shao Ying
Powiązania:
https://bibliotekanauki.pl/articles/27323651.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
modifier
hydration preparation
magnesium hydroxide
polypropylene
Opis:
With the rapid development of the polymer materials industry and the improvement of people's environmental awareness, magnesium hydroxide has been widely used in polymer materials due to its high decomposition temperature, non-toxic smoke suppression, and the advantages of neutralizing harmful gases produced by polymer combustion. However, the conventional preparation methods of magnesium hydroxide exhibit several issues, including high hydrophilicity, elevated polarity, and limited compatibility with polymers. This research proposes an improved method by adding sodium stearate and KH560 modifier, controlling the rate of magnesium oxide and preparing magnesium hydroxide flame retardants using a modifier-directed hydration method. Various characterizations confirmed its morphology, particle size and structure. The magnesium hydroxide exhibits low polarity, small particle size, stable structure and excellent hydrophobicity (with a contact angle of 120.32°, and a free energy of 1.34mN/m). In parallel, the magnesium hydroxide/polypropylene composites demonstrate excellent flame retardancy (LOI of 25%, V-1 grade) and simultaneously enhance the dispersion of magnesium hydroxide within the polypropylene matrix, improving the material's toughness and strength.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 6; art. no. 175706
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of grouting pressure volatility on additional response of adjacent pile foundation in shield construction
Autorzy:
Zhang, Chuan-Chuan
Li, Dan-Mei
Zhang, Jun
Yu, Tong-Sheng
Chen, Qiang
Powiązania:
https://bibliotekanauki.pl/articles/2086958.pdf
Data publikacji:
2022
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
grouting pressure fluctuations
adjacent loaded-pile foundation
normal distribution
FLAC3D
Opis:
Soil parameters along the heading direction are subjected to spatial variability during shield construction, so grouting pressure requires constant adjustment to ensure ground stress sta- bility. This causes grouting pressure to fluctuate around the design pressure/curve. There- fore, the influence of the grouting pressure volatility on the adjacent loaded-pile foundation should be considered in shield tunneling. In this study, a refined numerical simulation of the shield construction process is conducted using the Fast Lagrangian Analysis of Continua in Three Dimensions (FLAC3D) software. A total of 300 groups of grouting pressure pa- rameters with a skewed normal distribution are input into the numerical model. Then, the influence of the construction parameter uncertainty on the adjacent loaded-pile foundation is analyzed. Finally, the back analysis method is conducted based on the monitored data to evaluate how the construction process affects the pile foundation. The calculation results are compared with those of the traditional finite element method. The results indicate that in the tunneling process, the grouting pressure fluctuation greatly affects the additional bend- ing moment of the adjacent pile foundation. Under the influence of the grouting pressure, the additional axial force and additional bending moment of the pile foundation also follow the skewed normal distribution. The back analysis results of the pile foundation are greater than those of the typical numerical method by about 60% 100%, that is using the back analysis calculation results to evaluate the pile foundation additional response can reduce the risk.
Źródło:
Journal of Theoretical and Applied Mechanics; 2022, 60, 1; 33--47
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of unstable elements with different hardness on lower limb loading
Autorzy:
Li, F.
Mei, Q.
Gu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/307265.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ciśnienie podeszwowe
stopa
staw kolanowy
twardość
knee adduction moment
plantar pressure
unstable elements
hardness
foot
Opis:
Purpose: Osteoarthritis of the knee is one of the most common diseases. For this chronic disease, modified footwear structure can effectively prevent and relieve disease of the knee. The aim of this study was to explore the effects of shoe surface elastic modulus on external knee adduction moment and ground reaction force and foot loading characteristics. Methods: Sixteen healthy female volunteers were recruited, and each subject performed five walking trials under two shoes condition. The lower limb loading data was collected using force platform and in-sole pressure measurement system. Results: The results showed that the external knee adduction moment was decreased in all stance phase when wearing SS (unstable shoes with soft unstable elements), compared with HS (unstable shoes with hard unstable elements). The ground reaction force showed no obvious change under two shoes condition. Additionally, compared with HS, plantar pressure transferred from medial foot to lateral foot when wearing SS. Along with changes of contact areas, average pressure and impulse had also presented this tendency. Conclusions: These results can provide some scientific evidence and suggestions for footwear companies, and for the foot plantar medial injury disease has also certain applicability.
Źródło:
Acta of Bioengineering and Biomechanics; 2015, 17, 2; 85-92
1509-409X
2450-6303
Pojawia się w:
Acta of Bioengineering and Biomechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigations on the Spin-Hamiltonian Parameters and Local Structure of the Orthorhombic $Cu^{2+}$ Center in $PbTiO_3$ Crystal
Autorzy:
Chao-Ying, Li
Li-Bin, Cheng
Xue-Mei, Zheng
Powiązania:
https://bibliotekanauki.pl/articles/1400511.pdf
Data publikacji:
2015-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
76.30.Fc
75.10.Dg
71.70.Ch
Opis:
The spin-Hamiltonian parameters (the g factors $g_{i}$ and the hyperfine structure constants $A_{i}$, i = x, y, z) and local structure of the $Cu^{2+}$ center in $PbTiO_{3}$ are theoretically studied by using the perturbation formulae of these parameters for a $3d^{9}$ ion in an orthorhombically elongated octahedra. The orthorhombic center is attributed to $Cu^{2+}$ occupying the host $Ti^{4+}$ site associated with a nearest-neighbouring oxygen vacancy $V_{O}$ along the c-axis, and the impurity $Cu^{2+}$ off-center displacement $\Delta Z_{L}$ ( ≈0.18 Å) is smaller than that of the host $Ti^{4+}$ site ($\Delta Z_{H}$≈ 0.3 Å). Meanwhile, the planar $Cu^{2+}-O^{2-}$ bonds are found to experience the relative variation ΔR ( ≈ 0.098 Å) along the a- and b-axes, respectively, due to the Jahn-Teller effect and the size mismatching substitution of $Ti^{4+}$ by $Cu^{2+}$. The theoretical spin-Hamiltonian parameters based on the above defect structure agree well with the observed values.
Źródło:
Acta Physica Polonica A; 2015, 127, 6; 1671-1675
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonal characteristics of nutrient and nutrient structure in the Yangtze River estuary
Autorzy:
Li, Lei
Xv, Guodong
Zheng, Yingjie
Jiang, Mei
Powiązania:
https://bibliotekanauki.pl/articles/27311574.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Yangtze River estuary
nutrient
spatial distribution
temporal distribution
trophic structure
Opis:
This data article aimed to evaluate the influencing mechanisms of the nutrients and the level of eutrophication in the Yangtze River estuary. The seasonal characteristics of nutrients (dissolved inorganic nitrogen (DIN), SiO3-2–Si, and PO43-P) in the seawater of the Yangtze River estuary were analyzed by conducting surveys in spring and summer of 2019. The findings revealed that the concentrations of all nutrient at the surface and bottom layers were lower in spring compared to summer. NO3–N was typically the major form of DIN. Runoff was identified as the primary source of DIN and SiO32−–Si, while PO43−–P originated from a various sources. The SiO32−–Si, while PO43−–P values in the surface and bottom layers during the spring and summer were higher than the Redfield values, indicating an imbalanced nutrient distribution. Furthermore, discrepancies were observed in the distributions of DIN/PO43−–P, SiO32−–Si/DIN, and SiO32−–Si/PO43−–P in the Yangtze River estuary. Through an examination of the ratio of DIN/PO43−–P absorbed by phytoplankton, PO43−–P was identified as a potential limiting factor for nutrition in the sea area of the Yangtze River estuary during spring and summer. The Eutrophication Index (E) values for both spring and summer were found to be higher than the eutrophication threshold, indicating severe eutrophication in the studied sea area.
Źródło:
Archives of Environmental Protection; 2023, 49, 3; 115--122
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect and mechanism of surface pretreatment on desulfurization and desilication from low-grade high-sulfur bauxite using flotation
Autorzy:
Zhou, Jieqiang
Mei, Guangjun
Yu, Mingming
Li, Haonan
Powiązania:
https://bibliotekanauki.pl/articles/110740.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
bauxite
surface pretreatment
flotation
desulfurization and desilication
Opis:
Surface pretreatment using a hot alkaline solution was carried out to improve the effect of desulfurization and desilication on low-grade bauxite with high sulfur content. The results demonstrated that, after surface pretreatment, a maximum grade and recovery of 66.17% and 87.27%, respectively, were achieved, and the sulfur content and ratio of A/S were 0.19% and 7.09, respectively. The surface pretreatment mechanism was further analysed by XRD and SEM analyses. The improved results of desulfurization and desilication were attributed to the selective corrosion of aluminosilicate minerals in coarse particles, reducing the active silicon sites on the surface of coarse particles as well as enhancing the cation exchange between the collector and aluminosilicate minerals.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 4; 940-950
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Welding Heat Input on Microstructure and Corrosion Characterization in CGHAZ of X80 Pipeline Steel
Autorzy:
Wang, Xue-Mei
Zhao, Wei
Chen, Kai
Li, Zhen
Powiązania:
https://bibliotekanauki.pl/articles/28099607.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
X80 pipeline steel
coarse grain heat-affected zone
heat input
corrosion
Opis:
The coarse-grained heat-affected zone specimens of X80 pipeline steel were produced by welding thermal simulation under different heat inputs of 10, 30, and 55 kJ/cm to study the effects of heat input on microstructure evolution and corrosion characterization. The corrosion resistance of coarse-grained heat-affected zones was poorer than that of base metal due to less homogenous in the former. For 10 kJ/cm coarse-grained heat-affected zone, the corrosion resistance was poorer than the others due to the more adsorption hydrogen around the needle-like martensite/austenite constituents and greater galvanic driving force between the needle-like martensite/austenite constituents and ferrite. In carbonate/bicarbonate solution, better corrosion resistance for coarse-grained heat-affected zones was obtained when the heat input is 30 kJ/cm, which can be attributed to the severe coarse martensite/austenite constituents for 55 kJ/cm coarse-grained heat-affected zone. In the H2S environment, the better corrosion resistance for coarse-grained heat-affected zone was obtained when the heat input is 55 kJ/cm, which can be attributed to the protective effect of corrosion products. In addition, the high content of M/A constituents for 30 kJ/cm CGHAZ was good for hydrogen adsorption, which was adverse to the corrosion resistance in acid environments.
Źródło:
Archives of Metallurgy and Materials; 2023, 68, 2; 659--671
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The mechanism study on aryl-substituted aromatic acid ionic liquid as the collector for quartz flotation
Autorzy:
Li, Haonan
Mei, Guangjun
Yu, Mingming
Cheng, Qian
Zhu, Guobin
Powiązania:
https://bibliotekanauki.pl/articles/109922.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
ionic liquid
flotation collector
quartz
magnetite
Opis:
An aryl-substituted aromatic acid ionic liquid (M-X) was synthesized through hexadecyl trimethyl ammonium bromide and sodium salicylate, and it was employed as a flotation collector for the separation of quartz from magnetite. Laboratory flotation studies of magnetite and quartz were conducted using the M-X and dodecylamine (DDA) as collector. The results showed that the M-X has a stronger collecting ability and selectivity for quartz without starch. The adsorption mechanism of M-X on quartz and magnetite surfaces was studied by Fourier transform infrared spectroscopy (FTIR), zeta potential and X-ray photoelectron spectroscopy (XPS) analysis. Results indicated that the adsorption of M-X on the quartz surface was more efficient than that on the magnetite surface. And the salicylate anion in M-X was found to have depression effect to magnetite.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 5; 1239-1249
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research on the linear viscoelastic rheological properties of rejuvenated asphalt mastic based on the discrete element method
Autorzy:
Lin, Mei
Lei, Yu
Li, Ping
Shuai, Jun
Wang, Zhaoli
Powiązania:
https://bibliotekanauki.pl/articles/27312105.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
model konstytutywny
metoda elementów dyskretnych
mastyks asfaltowy odnowiony
właściwości reologiczne
constitutive model
discrete element method
rejuvenated asphalt mastic
rheological characteristics
Opis:
The rheological property of asphalt is an important factor affecting the pavement performance of asphalt binder, and the fundamental reason for the change of asphalt rheological property is the strong evolution of asphalt material meso structure. However, the internal mechanism of rejuvenated asphalt mastic system is complex and its rules are difficult to grasp. Aiming to study the relationship between meso mechanical parameters and rheological parameters of rejuvenated asphalt mastic, the meso structure model of rejuvenated asphalt mastic was established and improved based on the discrete element method. Moreover, the meso parameters of the model were obtained by the objective function method, and then the influences of various factors were studied to construct the mathematical constitutive model of rheological parameter modulus and meso mechanical parameters. Combing with the reliability of the improved Burgers model was verified based on the rheological test results of rejuvenated asphalt mastic. In addition, the virtual test of dynamic shear rheological dynamic frequency scanning was carried out on the asphalt mastic sample by particle flow software. By adjusting the mesomechanical parameters, the simulation results (complex shear modulus and phase angle) were consistent with the test results. This study clarified the relationship between mesomechanics and macro performance, and this model could be used to obtain the complex shear modulus of rejuvenated asphalt mastic under different types, filler-asphalt ratio and external force environments by adjusting particle flow, wall boundary and other conditions, which can greatly save the workload for the later research and provide a theoretical basis for production experiments.
Źródło:
Archives of Civil Engineering; 2023, 69, 2; 399--416
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A unified calculation of the optical and EPR spectral data for the trigonal Cr³⁺ center in Cr³⁺-doped α-RbAl(SO₄)₂·12H₂O alum crystal
Autorzy:
Li, Xiao-Wu
Mei, Yang
Wei, Cheng-Fu
Zheng, Wen-Chen
Powiązania:
https://bibliotekanauki.pl/articles/1070555.pdf
Data publikacji:
2016-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.70.Ch
76.30.Fc
78.40.Ha
78.55.Hx
Opis:
The optical band positions and the spin-Hamiltonian parameters (g factors g_{∥}, g_{⊥}, and zero-field splitting parameter D) of alum α-RbAl(SO₄)₂·12H₂O:Cr³⁺ are calculated by diagonalizing the 120× 120 complete energy matrix based on the two-spin-orbit-coupling-parameter model. The model takes into account not only the contributions due to the spin-orbit-coupling parameter of central d^{n} ion in the conventional crystal field theory, but also those due to ligands via covalence effect. The calculation indicates that the fourteen observed spectral data (eleven optical band positions and three spin-Hamiltonian parameters) can be reasonably and uniformly explained with four adjustable parameters (the Racah parameters B, C, intrinsic parameter A̅₄(R) in the superposition model, and the trigonal distortion angle β). The calculations also suggest that contrary to the previous findings, the trigonal distortion of Cr³⁺ (entering the Al³⁺ site in the host crystal) center in α-RbAl(SO₄)₂·12H₂O is induced mainly by the oxygen (or water) octahedron around the Cr³⁺ ion rather than the more distant neighbors.
Źródło:
Acta Physica Polonica A; 2016, 129, 3; 340-343
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristic of carbon dioxide absorption by cereals in Poland and China
Charakterystyka absorbcji dwutlenku węgla przez zboża w Polsce i Chinach
Autorzy:
Pawłowski, Lucjan
Pawłowska, Małgorzata
Cel, Wojciech
Wang, Lei
Li, Chong
Mei, Tingting
Powiązania:
https://bibliotekanauki.pl/articles/215903.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:
climate change
carbon dioxide emission
terrestrial ecosystem
carbon dioxide sequestration
photosynthesis
zmiana klimatu
emisja dwutlenku węgla
ekosystem lądowy
sekwestracja dwutlenku węgla
fotosynteza
Opis:
The reports of Intergovernmental Panel for Climate Change indicate that the growing emission of greenhouse gases, produced from the combustion of fossil fuels, mainly carbon dioxide, leads to negative climate changes. Therefore, the methods of mitigating the greenhouse gases emission to the atmosphere, especially of carbon dioxide, are being sought. Numerous studies are focused on so-called geological sequestration, i.e. injecting carbon dioxide to appropriate geological strata or ocean waters. One of the methods, which are not fully utilized, is the application of appropriate techniques in agriculture. The plant production in agriculture is based on the absorption of carbon dioxide in the photosynthesis process. Increasing the plant production directly leads to the absorption of carbon dioxide. Therefore, investigation of carbon dioxide absorption by particular crops is a key issue. In Poland, ca. 7.6 mln ha of cereals is cultivated, including: rye, wheat, triticale, oat and barley. These plants absorb approximately 23.8 mln t C annually, including 9.8 mln t C/yr in grains, 9.4 mln t C/yr in straw and 4.7 mln t C/yr in roots. The China, these cereals are cultivated on the area over 24 mln ha and absorb 98.9 mln t C/yr, including 55 mln tC/yr in grains, 36 in straw, and 7.9 mln t C/yr in roots. The second direction for mitigating the carbon dioxide emission into the atmosphere involves substituting fossil fuels with renewable energy sources to deliver primary energy. Cultivation of winter cereals as cover crops may lead to the enhancement of carbon dioxide removal from the atmosphere in the course of their growth. Moreover, the produced biomass can be used for energy generation.
Z raportów Międzynarodowego Zespołu ds. Zmian Klimatu (IPCC) wynika, że rosnąca emisja gazów cieplarnianych, głównie dwutlenku węgla pochodzącego ze spalania paliw kopalnych, prowadzi do negatywnych zmian klimatu. Wobec takiego zagrożenia poszukuje się metod prowadzących do ograniczenia emisji do atmosfery gazów cieplarnianych, w szczególności dwutlenku węgla. Badania nad ograniczeniem emisji dwutlenku węgla koncentrują się głównie nad tzw. sekwestracją geologiczną, czyli zatłaczaniem dwutlenku węgla do odpowiednich pokładów geologicznych lub wód oceanicznych. Jednym ze sposobów, nie w pełni wykorzystanych, jest stosowanie odpowiednich technik w rolnictwie. Roślinna produkcja w rolnictwie oparta jest na absorpcji dwutlenku węgla w procesie fotosyntezy. Zwiększenie produkcji roślinnej prowadzi bezpośrednio do wzrostu absorpcji dwutlenku węgla. Dlatego ważnym zagadnieniem jest poznanie absorpcji dwutlenku węgla przez poszczególne uprawy. W Polsce na obszarze o powierzchni 7,6 mln ha uprawia się zboża: żyto, pszenicę, pszenżyto, owies i jęczmień. Rośliny te absorbują rocznie około 23,8 mln t C, z tego 9,8 mln t C/rok w ziarnach, 9,4 mln t C/rok w słomie i 4,7 mln t C/rok w korzeniach. W Chinach zboża te uprawiane są na powierzchni przekraczającej 24 mln ha i absorbują 98,9 mln t C/rok, z tego w ziarnach 55 mln t C/rok, w słomie 36 mln t C/rok, a 7,9 mln t C/rok w korzeniach. Drugim kierunkiem ograniczania emisji dwutlenku węgla do atmosfery jest zastępowanie paliw kopalnych, stanowiących źródło energii pierwotnej, przez odnawialne źródła energii. Uprawa zbóż ozimych jako roślin okrywowych może prowadzić do intensyfikacji usuwania dwutlenku węgla z atmosfery. Ponadto wyprodukowana biomasa może być wykorzystana jako surowiec do produkcji energii.
Źródło:
Gospodarka Surowcami Mineralnymi; 2019, 35, 1; 165-176
0860-0953
Pojawia się w:
Gospodarka Surowcami Mineralnymi
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ribosomal proteins L34 and S29 of amphioxus Branchiostoma belcheri tsingtauense: cDNAs cloning and gene copy number
Autorzy:
Liu, Lina
Zhang, Shicui
Liu, Zhenhui
Li, Hongyan
Liu, Mei
Wang, Yongjun
Ma, Lifang
Powiązania:
https://bibliotekanauki.pl/articles/1041331.pdf
Data publikacji:
2005
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
amphioxus
ribosomal protein
S29
copy number
Branchiostoma
L34
Opis:
The complete cDNA and deduced amino-acid sequences of ribosomal proteins L34 (AmphiL34) and S29 (AmphiS29) from the amphioxus Branchiostoma belcheri tsingtauense were identified in this study. The AmphiL34 cDNA is 435 nucleotides in length and encodes a 118 amino-acid protein with calculated molecular mass of 13.6 kDa. It shares 53.6-67.5% amino-acid sequence identity with its eukaryotic counterparts including human, mouse, rat, pig, frog, catfish, fruit fly, mosquito, armyworm, nematode and yeast. The AmphiS29 cDNA comprises 453 nucleotides and codes for a 56 amino-acid protein with a calculated molecular mass of 6.6 kDa. It shows 66.1-78.6% amino-acid sequence identity to eukaryotic S29 proteins from human, mouse, rat, pig, zebrafish, seahorse, fruit fly, nematode, sea hare and yeast. AmphiL34 contains a putative nucleolar localization signal, while AmphiS29 has a zinc finger-like domain. A phylogenetic tree deduced from the conserved sequences of AmphiL34 and AmphiS29 and other known counterparts indicates that the positions of AmphiL34/AmphiS29 are intermediate between the vertebrate and invertebrate L34/S29. Southern blot analysis demonstrates the presence of one copy of the L34 gene and 2-3 copies of the S29 gene in the genome of the amphioxus B. belcheri tsingtauense. This is in sharp contrast to the existence of 7-9 copies of the L34 gene and 14-17 copies of the S29 gene in the rat genome. These date suggest that housekeeping genes like AmphiL34 and AmphiS29 have undergone large-scale duplication in the chordate lineage.
Źródło:
Acta Biochimica Polonica; 2005, 52, 4; 857-862
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis of a novel hydroxamic acid flotation collector and its flotation separation of malachite against quartz
Autorzy:
Sun, Xin
Huang, Lingyun
Wu, Dandan
Hu, Bo
Zhang, Mei
Li, Yaming
Tong, Xiong
Powiązania:
https://bibliotekanauki.pl/articles/2146909.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation
collector
malachite
hydroxamic acid
direct flotation
adsorption
Opis:
This paper proposes a promising chelating collector, phenyl propyl hydroxamic acid (BPHA), to directly float malachite for the separation of malachite against quartz. The flotation performance and mechanism was investigated via microflotation tests, as well as through contact angle, Scanning Electron Microscopeand Energy Dispersive Spectrometer (SEM–EDS), zeta potential, adsorption capacity, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. The results of microflotation tests showed that BPHA has a strong ability to collect malachite and a significant selectivity against quartz. The contact angle tests showed that BPHA effectively adsorbed onto the mineral surface and could improve the hydrophobicity of the malachite surface. SEM–EDS and adsorption capacity analyses further indicated that BPHA adsorbed onto the surface of malachite. The FR-IR results suggested that BPHA could react with Cu2+ ions and facilitate strong chemical adsorption onto the surface of malachite. Furthermore, zeta potential and XPS analyses provided clear evidence that BPHA exhibited a stronger affinity for malachite and a weaker interaction with quartz.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 4; art. no. 149427
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł

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