Wyniki wyszukiwania - Biblioteka Nauki

1

An asymmetrical bolt supporting design of retreating coal roadway based on physical simulation in large dip coal seam

100%

Yang K. , Xie G. X.

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tom Vol. 36, no. 3

453-461

EN

With the coal inclination increasing, how to design bolt supporting parameters is key to control stablity of retreating entry because of lower-rib and upper-rib in unsymmetrical trapezoid. According to geological and technical conditions of large deep coal seams (LDCS) whose angle is from 25 degrees to 45 degrees in Huainan Coal Mines, physical model was used to simulate configuration and mechanical characteristics of coal roadway with bolt supporting. Based experimental data analyzing, patterns of deformation, displacement, failure, and mining-induced stress (MIS) of rock surrounding roadway are unsymmetrical. The results show that the roof and upper-rib of solid roadway are the main supporting section but, roadway of gob-side with small width pillar prevention, the roof and lower-rib are the key sections. So aimed at dissymmetrical strata behaviors and mechanical characteristics, the asymmetrical bolt supporting (ABS) parameters were designed and put forward in engineering. Engineering practice show that ABS is suitable and reliable in controlling rock stability in LDCSs mining.

PL

W przypadku nachylonych pokładów węglowych ważne jest odpowiednie zaprojektowanie parametrów obudowy celem zapewnienia kontroli stabilności chodnika, ponieważ dolne i górne żebra tworzą układ trapezoidalny. W zależności od warunków geologiczno technicznych w kopalni Huainan Coal Mines, gdzie upad pokładów węglowych (LDCS) waha się w granicach 25 stopni do 45 stopni, zaprojektowano model służący do stymulowania konfiguracji oraz charakterystyki mechanicznej chodnika z obudową śrubową. Na podstawie danych doświadczalnych ustalono, że układy deformacji, przemieszczenia, uszkodzenia i naprężenie górotworu (MIS) są asymetryczne. Wyniki przeprowadzonych badań wykazały, że strop oraz żebro górne chodnika stanowią zasadniczą strefę podporu, ale w przypadku chodników słabo zabezpieczonych stemplami, strop i dolne żebro odgrywają strefę kluczową. W związku z tym, dla warunków pokładów asymetrycznych o zmiennej charakterystyce mechanicznej zaprojektowano i przekazano do wykonania system obudowy asymetrycznej (ABS). Praktyka wykazała, że system APS jest niezawodny w przypadku kontroli stabilności skał w górnictwie LDCS.

2

The differential antioxidant capacity of watermelon flesh at different maturity stages and its inhibitory effects on seed aging may explain the significance of fruit flesh colors

80%

Deng B. , Zhang Y. , Yang K. , Li Z.

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nr 06

3

Analysis and Prediction of the Dynamic Heat - Moisture Comfort Property of Fabric

71%

Yang K. , Jiao M. J. , Chen Y. S. , Li J. , Zhang W.-Y.

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tom Vol. 16, no. 3 (68)

51--55

EN

A series of experiments and analyses were performed to study the dynamic heat and moisture transferring procedure as well as evaluate the heat-moisture comfort property of fabric in wearing conditions that produce continued sweat. By measuring five static indexes of ten different fabrics, which involved static heat-moisture transmission through fabric, as well as two dynamic comprehensive indexes obtained from the dynamic curves using a self-made microclimate measuring apparatus, the relation between the static indexes and dynamic comprehensive indexes was established.In addition, an evaluation and prediction system for the dynamic heat-moisture comfort property of the textile was formulated by means of the grey system theory. For two different environmental conditions: the most comfortable ones, and an extremely uncomfortable condition for humans, four different prediction models were built, and high predictive precision was obtained.

PL

Przeprowadzono serię eksperymentów a następnie je przeanalizowano dla określenia dynamicznego transportu ciepła i wilgoci poprzez tkaniny, jak również oceny właściwości komfortu cieplnego i wilgotnościowego tych tkanin w takich warunkach użytkowania, w których występuje wytwarzanie potu przez użytkownika ubrań. Mierzono 5 parametrów statycznych dla 10 rożnych tkanin określających statyczne stany przepływów ciepła i wilgoci przez tkaninę, jak również dwa dynamiczne współczynniki określane na podstawie krzywych temperatury i wilgotności w czasie. Zastosowano własnej budowy aparat umożliwiający wytworzenie mikroklimatu oraz określanie zależności pomiędzy poszczególnymi parametrami statycznymi i dynamicznymi. Dodatkowo opracowano system oceny cieplnego i wilgotnościowego komfortu dynamicznego tekstyliów stosując teorię „szarego systemu” dla dwóch różnych warunków otoczenia – bardzo komfortowych i ekstremalnie nie komfortowych dla człowieka- opracowano 4 różne przewidywane modele uzyskując dużą precyzję przewidywania.

4

Impacts of dissolved oxygen and initial sludge concentrations on aerobic stabilization of sewage sludge

71%

Ji B. , Yang K. , Chen W. , Wang J. , Zhu L.

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2016

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tom 25

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nr 1

EN

Impacts of dissolved oxygen (DO) and initial sludge concentrations on aerobic digestion for sewage sludge treatment were studied without adding alkalis. The MLVSS removal efficiencies were 50% and 47% in 20 days when DO concentrations were about 5.0 and 7.0 mg/L, respectively. Value of pH increased slightly in the first 6 days and then dropped constantly. The decrease of MLVSS appeared first quick back slow trend during the process and the OUR declination was similar. At the same DO level of 5.0 mg/L, the lower initial sludge concentration favored the efficiency of sludge stabilization. Both TN and TP of the supernatant were continually increasing and the ultimate concentrations were three to four times the initial concentrations. Results obtained from the present work could provide basic information for the aerobic sludge treatment process.

5

Selective reduction of PbSO4 to PbS with carbon and flotation treatment of synthetic galena

61%

Zheng Y.-X. , Liu W. , Qin W.-Q. , Han J.-W. , Yang K. , Luo H.-L.

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tom Vol. 51, iss. 2

535--546

EN

In order to recover lead from the zinc leaching residues, a new technology involving selective reduction of lead sulfate to lead sulfide with carbon followed by flotation was investigated. The reduction thermodynamics of PbSO4 was discussed and the effects of molar ratio of C to PbSO4, reaction temperature and time were examined by thermogravimetry (TG) and XRD. Verification tests were further carried out to prove the conclusions of thermodynamic and TG analyses, and the transformation extent could reach 86.45% under the optimal roasting conditions. The prepared galena was then subjected to micro-flotation tests, and the highest lead recovery could reach up to 75.32%.

6

Research on the statistical characteristics of crosstalk in naval ships wiring harness based on Polynomial Chaos Expansion method

61%

Chi Y. , Li B. , Yang X. , Wang T. , Yang K. , Gao Y.

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tom S 2

205--214

EN

Crosstalk in wiring harness has been studied extensively for its importance in the naval ships electromagnetic compatibility field. An effective and high-efficiency method is proposed in this paper for analyzing Statistical Characteristics of crosstalk in wiring harness with random variation of position based on Polynomial Chaos Expansion (PCE). A typical 14-cable wiring harness was simulated as the object of research. Distance among interfering cable, affected cable and GND is synthesized and analyzed in both frequency domain and time domain. The model of naval ships wiring harness distribution parameter was established by utilizing Legendre orthogonal polynomials as basis functions along with prediction model of statistical characters. Detailed mean value, mean square error, probability density function and reasonable varying range of crosstalk in naval ships wiring harness are described in both time domain and frequency domain. Numerical experiment proves that the method proposed in this paper, not only has good consistency with the MC method can be applied in the naval ships EMC research field to provide theoretical support for guaranteeing safety, but also has better time-efficiency than the MC method. Therefore, the Polynomial Chaos Expansion method.

7

The impacts of crustacean zooplankton on a natural ciliate community: a short-term incubation experiment

51%

Li J. , Yang K. , Chen F. , Lu W. , Fang T. , Zhao X. , Li H. , Cui K.

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nr 4

8

Cloning and expression of cold-inducible RNA binding protein in domestic yak (Bos grunniens)

51%

Yang K. , Zhang Q. , Wen Z. , Pan Y. , Yu S. , He J. , Yang X. , Liu P. , Cui Y.

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nr 4

EN

Cold-inducible RNA binding protein (CIRP) is over-expressed during cold and many other stresses, and could regulate the adaptation to hypothermia. In the present investigation, the objective was to determine the expression of CIRP in adult yak heart, liver, spleen, lung, kidney, brain, ovary, testis and skin by relative quantitative real time polymerase chain reaction (RT-PCR), Western blot and immunohistochemistry from mRNA and protein levels. The CIRP open reading frame encoding was cloned from the domestic yak brain. Results of RT-PCR and Western blot showed the high expression level of CIRP in the heart, kidney, brain, testis and skin, and the lower expression level of CIRP in the lung. Immunohistochemical staining showed CIRP was expressed in the nucleus of neuronal cells, spermatogonia, primary spermatocytes and epidermal cells, and in the cytoplasm of the residual tissues. These observations may provide new data to understand and further study the important role of CIRP protein in the plateau adaptation of the domestic yak on long-term evolution. (Folia Morphol 2016; 75, 4: 460–466)

9

Expression and distribution of HIF-1alpha, HIF-2alpha, VEGF, VEGFR-2 and HIMF in the kidneys of Tibetan sheep, plain sheep and goat

51%

Yang K. , Zhang Z. , Li Y. , Chen S. , Chen W. , Ding H. , Tan Z. , Ma Z. , Qiao Z.

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tom 79

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nr 4