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1

Synteza matrycowa kompozytów tlenku cynku stosowanych w ogniwach słonecznych uczulanych barwnikiem

Zhao N., Zhang C., Zhang P.

Przemysł Chemiczny

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2018

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T. 97, nr 2

195--199

PL

Tlenek cynku jest obiecującym materiałem do budowy anod ze względu na możliwość uzyskiwania go w postaci różnych nanostruktur oraz doskonałą ruchliwość elektronów. W celu poprawy działania ogniw fotowoltaicznych otrzymano nanostruktury ZnO i zastosowano je w elektrodach półprzewodnikowych. Jako podłoże warstwy ZnO zastosowano szkło z tlenku cyny domieszkowanego fluorem FTO (fluorine-doped tin oxide). Po wyżarzaniu pokryto je warstwą składającą się z mikrokulek polistyrenowych wytworzonych in situ metodą polimeryzacji wolnorodnikowej. Zarodki ZnO hodowano w mieszaninie azotanu cynku i heksametylenotetraaminy w celu wytworzenia różnych typów nanostruktur ZnO (struktura siatki 3D i struktura nanodrutu-nanocząstki) o dużej powierzchni właściwej. Warstwę kompozytową uczulono barwnikiem N719 i zastosowano w ogniwach słonecznych. Uzyskano efektywność konwersji energii 3,91%.

EN

ZnO was deposited from Zn(OAc)2 soln. on F-doped SnO glass substrate by spin coating. After the procedure was repeated 4 times, the layer was annealed at 400°C for 1 h and covered with template layer consisting of polystyrene microspheres in-situ produced by free radical emulsion polymerization. The seed layer was grown in the mixt. of Zn(NO3)2 and hexamethylenetetramine to produce ZnO of nanowire-nanoparticle structures with high sp. surface area. The template layer was then removed by heating at 500°C for 1 h under formation of ZnO nanostructures. Di(tetrabutylammonium)cis-bis(isothiocyanato)bis(2,2’- bipyridyl-4,4’-dicarboxylato)ruthenium(II) (N719 dye) was then deposited from its soln. on the composite surface and sensitized in dark for 1 h. The product was characterized by X-ray diffractometry, elec. impedance spectroscopy and scanning electron microscopy and then successfully used as a semiconductor electrode in a solar cell of improved performance.

2

An improved resonant thermal converter based on micro-bridge resonator

Dong L., Han J., Zhang P., Zhao Z., Cheng B., Han D.

Metrology and Measurement Systems

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2018

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Vol. 25, nr 4

715--725

EN

This paper presents the design, fabrication and testing of an improved thin-film thermal converter based on an electro-thermally excited and piezo-resistively detected micro-bridge resonator. The resonant thermal converter comprises a bifilar heater and an opposing micro-bridge resonator. When the micro-bridge resonator absorbs the radiant heat from the heater, its axial strain changes, then its resonant frequency follows. Therefore the alternating voltage or current can be transferred to the equivalent DC quantity. A non-contact temperature sensing mechanism eliminates heat loss from thermopiles and reduces coupling capacitance between the temperature sensor and the heater compared with traditional thin-film thermal converters based on thermopiles. In addition, the quasi-digital output of the resonant thin-film thermal converter eliminates such problems as intensity fluctuations associated with analogue signals output by traditional thin-film thermal converters. Using the fast-reversed DC (FRDC) method, the thermoelectric transfer difference, which determines the frequency-independent part of the ac-dc transfer difference, is evaluated to be as low as 1.1 · 10-6. It indicates that the non-contact temperature sensing mechanism is a feasible method to develop a high-performance thermal converter.

3

Time-dependent reliability of spur gear system based on gradually wear process

Zhu L., Zhang Y., Zhang R., Zhang P.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 2

207--218

EN

To study dynamic evolution law of mechanical reliability caused by wear, gear transmission system is taken as a research object. Considering the effect of clearance caused by wear on gear teeth load in double meshing area, the formula of dynamic distribution load which is undertaken by two adjacent teeth is deduced. And the distributed pressure and meshing speed, which should be taken into account while calculating gear wear, are obtained based on the Winkler surface model and principle of tooth mesh. Based on the Archard’s wear model, numerical simulation model for wear in spur gear is deduced, and the wear depth of each meshing points on teeth outline with different wear cycles are obtained. The calculation wear model is replaced with a surrogate model with Neural Network and Kriging method to overcome time-consuming defect. Random process model is integrated with the surrogate model, and dynamic reliability for nonlinear stochastic structure with unknown distribution characteristic is obtained with Neural Network-based Edgeworth series technique and four moment methods, which is compared with Kriging-based Monte Carlo simulation method. The computational efficiency and accuracy are also demonstrated.

PL

W artykule badano prawo dynamicznej ewolucji niezawodności mechanicznej powodowanej zużyciem na przykładzie układu przekładni zębatej. Na podstawie rozważań nad wpływem luzu powstałego na skutek zużycia na obciążenie zębów przekładni w obszarze podwójnych zazębień, wyprowadzono wzór na dynamiczny rozkład obciążeń przyjmowanych przez pary sąsiadujących zębów. Rozłożone naciski i prędkość zazębiania, które należy uwzględnić przy obliczaniu zużycia przekładni, otrzymano na podstawie modelu powierzchniowego Winklera oraz zasady zazębienia. W oparciu o model zużycia Archarda, wyprowadzono numeryczny model symulacyjny zużycia w przekładni zębatej oraz obliczono głębokość zużycia każdego z punktów zazębienia na zarysie zębów przy różnych cyklach zużycia. Aby uniknąć problemu czasochłonności, obliczeniowy model zużycia zastąpiono modelami zastępczymi bazującymi na sieci neuronowej i metodzie krigingu. Model procesu losowego zintegrowano z modelem zastępczym, a dynamiczną niezawodność dla nieliniowej struktury stochastycznej o nieznanej charakterystyce rozkładu uzyskano za pomocą techniki serii Edgeworth opartej na sieci neuronowej oraz metody czterech momentów, którą porównano z metodą symulacji Monte Carlo opartą na krigingu. Wykazano także wydajność obliczeniową i dokładność omawianej metody.

4

Dispersion features of transmitted channel waves and inversion of coal seam thickness

Hu Z., Zhang P., Xu G.

Acta Geophysica

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2018

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Vol. 66, no. 5

1001--1009

EN

In-seam seismic survey currently is a hot geophysical exploration technology used for the prediction of coal seam thickness in China. Many studies have investigated the relationship between the group velocity of channel wave at certain frequency and the actual thickness of exposed coal beds. But these results are based on statistics and not universally applicable to predict the thickness of coal seams. In this study, we first theoretically analyzed the relationship between the depth and energy distribution of multi-order Love-type channel waves and found that when the channel wave wavelength is smaller than the thickness of the coal seam, the energy is more concentrated, while when the wavelength is greater than the thickness, the energy reduces linearly. We then utilized the numerical simulation technology to obtain the signal of the simulated Love-type channel wave, analyzed its frequency dispersion, and calculated the theoretical dispersion curves. The results showed that the dispersion characteristics of the channel wave are closely related to the thickness of coal seam, and the shear wave velocity of the coal seam and its surrounding rocks. In addition, we for the first time realized the joint inversion of multi-order Love-type channel waves based on the genetic algorithm and inversely calculated the velocities of shear wave in both coal seam and its surrounding rocks and the thickness of the coal seam. In addition, we found the group velocity dispersion curve of the single-channel transmitted channel wave using the time–frequency analysis and obtained the phase velocity dispersion curve based on the mathematical relationship between the group and phase velocities. Moreover, we employed the phase velocity dispersion curve to complete the inversion of the above method and obtain the predicted coal seam thickness. By comparing the geological sketch of the coal mining face, we found that the predicted coal seam thickness is in good agreement with the actual thickness. Overall, adopting the channel wave inversion method that creatively uses the complete dispersion curve can obtain the shear wave velocities of the coal and its surrounding rocks, and analyzing the depth of the abruptly changed shear wave velocity can accurately obtain the thickness of the coal seam. Therefore, our study proved that this inversion method is feasible to be used in both simulation experiments and actual detection.

5

Żelowanie opartych na naftalenie oligoamidów w rozpuszczalnikach polarnych i niepolarnych

Luo K., Zhang P., Yue Y., Yuan X., Yuan L., Feng W.

Przemysł Chemiczny

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2017

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T. 96, nr 9

1906--1912

PL

Pojedyncze dwucząsteczkowe asocjaty oligoamidu opartego na naftalenie, zawierające wzajemnie niekomplementarne sekwencje wiązań wodorowych przekształcano w organożele w procesach samoorganizacji zarówno w rozpuszczalniku niepolarnym (chlorobenzen), jak i polarnym (metanol), czego nie dało się osiągnąć w przypadku asocjatów oligoamidów opartych na benzenie, zawierających komplementarne (dopasowane) sekwencje wiązań wodorowych. Metodą skaningowej mikroskopii elektronowej wykazano, że samoorganizujące się struktury były splątanymi sieciami o rozmiarach nanometrycznych.

EN

Single naphthalene-based oligoamide strands were arrayed in a non-complementary sequence self-assembling into organogels in either non-polar solvent (PhCl) or polar solvent (MeOH), what was otherwise impossible with the PhH-based oligoamide strands with complementary H-bonding sequences (R.K. Cao et al., 2010). The selfassembled structures of the compds. revealed nano-sized entangled networks when examd. by scanning electron microscopy.

6

Influences of a visco-elastically supported boundary on reflected waves in a couple-stress elastic half-space

Wang C. D., Wei P. J., Zhang P., Li Y. Q.

Archives of Mechanics

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2017

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Vol. 69, nr 2

131--156

EN

The reflection of elastic waves at the surface of a couple-stress elastic half-space with a viscoelastic support is studied in this paper. Different from the classical elastic solid, there are: a non-dispersive dilatational propagating wave, a dispersive transverse propagating wave and a dispersive evanescent wave in a couple-stress elastic solid. The boundary conditions at the visco-elastically supported surface of a couple-stress elastic half-space include the couple-stress vector and the rotation vector, which disappear in the classical elastic solid. They are used to obtain a set of linear algebraic equation, from which the amplitude ratios of reflection waves with respect to the incident wave can be determined. Then, the reflection coefficients in terms of energy flux ratios are calculated numerically, and the normal energy flux conservation is used to validate the numerical results. At last, the influence of the boundary parameters that reflect the mechanical behavior of a viscoelastic support on the amplitude ratio, the phase shift and the energy partition of reflection waves are discussed based on the numerical results. Both the incident longitudinal displacement wave (the P-wave) and incident transverse displacement wave (the SV-wave) are considered. It is found that the instantaneous elasticity and the delayed viscosity of a viscoelastic support have different influences on the reflection waves.

7

Optical image encryption by using diffractive imaging with special constraint in the input plane

Wang Z., Wang H., Yang X., Zhang P., Hou C., Qin Y.

Optica Applicata

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2016

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Vol. 46, nr 1

57--69

EN

In order to simplify the optical setup and the encryption process, a diffractive-imaging-based optical encryption system using a single diffraction pattern is proposed. A predesigned binary mask is placed before the plaintext in the encryption process, and three randomly distributed phase only masks are placed in the optical path. Only one diffraction pattern needs to be recorded as ciphertext by CCD. In the decryption process, an iterative phase retrieval algorithm is applied, in which the predesigned binary mask acts as a support constraint in the input plane. After the iterative process, an interpolation operation for the zero-valued pixels is also implemented. The effectiveness and robustness of the proposal are demonstrated by numerical simulation results.

8

Research on the Mechanism and Kinetics of Polymorphic Transitions of ε CL-20 in Composite Systems

Guo X.-Y., Zhang P., Xu J.-J., Wang Z.-H., Jiao Q.-J.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 4

689--702

EN

In order to explore the polymorphic transition law for ε-CL-20 in composite systems, the polymorphic transition process of pure ε-CL-20 crystals stimulated by heat was investigated by the X-ray Diffraction (XRD) method, and the kinetic parameters of the polymorphic transition process were calculated (including the apparent activation energy Ea and the pre-exponential factor lnA). Meanwhile the effects of different additives on the polymorphic transition process and kinetics of ε-CL-20 were explored in detail. The experimental results showed that the ε-form tends to transform into the γ- form on heating and that the Ea and lnA for the transition process were 209.97 kJ/mol and 57.47, respectively. The first group of additives clearly promoted the polymorphic transition of ε-CL-20 and lowered the initial transition temperature and the activation energy. The second and third groups of additives inhibited the polymorphic transition of ε-CL-20 and raised the initial transition temperature and the activation energy.

9

Research on Coverage Performance of GNSS

Zhang P., Xu C., Hu C., Chen Y.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

67--70

EN

The theory of Ground Coverage Performance (GCP) and Space Coverage Performance (SCP) of GNSS constellations is analysed. These performances are influenced by restriction of both the signal’s beam angle and the mask angle which is used by the receivers of users. Then the judgment methods and simulation results are acquired. In practical application, relevant constellations should be selected according to different tasks which are based on the simulation results to ensure the maximum number of visible satellites at the same time.

PL

Przeanalizowano teoretycznie obszary zasięgu naziemne (GCP) i w przestrzeni około-ziemskiej (SCP) dla konstelacji nadajników satelitarnych systemów nawigacji (GNSS). Sprawność zasięgu jest ograniczona zarówno przez kąt promieniowania nadajnika, jak i przez kąt zasięgu odbiorników użytkownika. Przedstawiono metody oceny i wyniki symulacji. W praktycznych zastosowaniach, w zależności od różnych zadań i wyników symulacji, konstelacja satelitów musi być dobrana tak, aby była widoczna maksymalna ich ilość w tym samym czasie. Badania dotyczą systemów: GPS, GLONASS, GALILEO i chińskiego BD2.

10

Controllable preparation of highly active horseradish peroxidase-gold nanoparticle bionanoconjugate

Zhang P., Liu Ch., Song S., Peng Ch.

Polish Journal of Chemical Technology

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2012

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Vol. 14, nr 4

57-60

EN

A novel method of immobilizing horse radish peroxidase enzyme (HRP) onto the surface of gold nanoparticles (GNPs) was developed. As a result, a high-activity bionanoconjugates was obtained through utilizing the biotin-streptavidin (SA) system. The HRP-SA-GNP bionanoconjugate with high activity was conveniently prepared through the biotin- avidin system. Compared with the HRP-GNP bioconjugate prepared through the traditional electrostatic absorption method, the enzyme activity per GNPs of this new bionanoconjugate was enhanced by 10 times. Moreover, the enzyme activity of this bionanoconjugate was controllable. The above method of bionanoconjugation preparation has promising applications In the fi elds including preparing highly active bio-nanoprobe and immobilized enzyme.

11

Influence of Bi2O3 addition on structure and dielectric properties of Ag(Nb0.8Ta0.2)O3 ceramics

Cao L., Li L., Zhang P., Wang H.

Materials Science Poland

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2011

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Vol. 29, No. 1

1--8

EN

The structure and dielectric properties of perovskite Ag(Nb0.8Ta0.2)O3 ceramics were explored. A small amount of Bi2O3 was used to modify the dielectric properties of the ceramics. The addition of Bi2O3 led the ceramics to a high densification and optimal dielectric properties. With the addition of 4.5 wt% Bi2O3, the permittivity of Ag(Nb0.8Ta0.2)O3 ceramics increased from 470 to 733, the dielectric loss decreased from 62×10-4 to 6.7×10-4, and the temperature coefficient of capacitance, TCC, decreased from 2004 ppm/°C to -50 ppm/°C. The high permittivity obtained was due to the high densification and weak Ta-O or Nb-O bond strength in the oxygen octahedron that results from the addition of Bi2O3.

12

An experimental investigation into the radial compressive properties of the biodegradable braided regeneration conduits for peripheral nerve repair

Liu G., Hu H., Zhang P., Wang W.

Autex Research Journal

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2005

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Vol. 5, no. 2

106--112

EN

Different regeneration conduits braided from biodegradable material poly (glycolide-co-L-lactide) (PGLA) for peripheral nerve repair and their radial compressive properties are presented. The influences of the braided structure and braiding angle are discussed. The results have shown that the nerve conduit braided with the triaxial structure at 60 degrees of the braiding angle has a greater ability to resist radial compression.

13

Orlicz-Bochner sequence spaces that have the uniform λ-property

Shi Z., Zhang P.

Annales Societatis Mathematicae Polonae. Seria 1: Commentationes Mathematicae

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2004

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Vol. 44, nr spec.

215-227

EN

Necessary and sufficient conditions in order that Orlicz-Bochner sequence spaces equipped with Luxemburg norm have the uniform [lambda] property are given.