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1

Influence of Polytetrafluorethylene on the Mechanical and Safety Properties of a Composite Modified Double Base Propellant

Sun S., Zhang T., Zhao B., Zhang G., Li X., Luo Y.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 3

468--484

EN

A novel Composite Modified Double Base (CMDB) propellant, formed by mechanically mixing aluminium/polytetrafluorethylene (Al/PTFE) powders, was prepared through a rolling process. A variety of tests, such as tensile properties, particle size analysis etc., were carried out to study the influence of PTFE on the CMDB propellant properties. The PTFE deformed from particles to fibres under a uniform shear force, forming a fibre network which greatly improved the propellant’s mechanical properties. Compared to that of the CMDB propellant without PTFE, the elongation of the propellant containing 6% PTFE was increased by 26 times, and moreover, the impact strength was enhanced by 326% at −40 °C. Significantly, the propellant friction and impact sensitivities were reduced by 75.8% and 35.6%, respectively. In addition, the presence of PTFE in the propellant resulted in fluorination of the Al. The gaseous combustion product AlF3 reduced the propellant combustion agglomeration. Consequently, PTFE significantly promoted the propellant’s mechanical performance, decreased the shock (friction, impact) sensitivity and reduced combustion agglomeration.

2

Study of the impact of 220 kV SISFCL on the distance protection for transmission line

Luo Y., Shi T., Huang L.

Archives of Electrical Engineering

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2018

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Vol. 67, nr 1

151--163

EN

As the most typical application of superconducting technology, the Saturated Iron core Superconducting Fault Current Limiter (SISFCL) is a kind of ideal high voltage limiter, which can achieve noticeable limiting endless stream and has wide application prospect. However, the selectivity and sensitivity of the distance protection (DP) in the high voltage transmission network would be affected by the impedance characteristics of SISFCL. For these problems, firstly the structure and the working principle of the SISFCL are introduced briefly. Secondly, the impact mechanisms of 220 kV SISFCL on the original distance protection for the transmission line (TL) are analyzed. Then two methods of eliminating influences are deduced from the previous analysis and an improved setting method based on SISFCL for distance protection is proposed. Finally, we used EMTDC/PSCAD software to build the 220 kV SISFCL and distance protection model in the transmission network. The simulation results demonstrate that the proposed setting strategy can effectively improve the selectivity and sensitivity of distance protection and provide a reference for the practical applications of SISFCL applied to the transmission line.

3

Research on the Mechanical Properties and Curing Networks of Energetic GAP/TDI Binders

Ma S., Li Y., Li Y., Li G., Luo Y.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

708--725

EN

This research focused on correlations between the macroscopic mechanical performance and microstructures of energetic binders. Initially a series of glycidyl azide polymer (GAP)/toluene diisocyanate (TDI) binders, catalyzed by a mixture of dibutyltin dilaurate (DBTDL) and triphenyl bismuth (TPB), was prepared. Uniaxial tensile testing, and low-field nuclear magnetic resonance and infrared spectroscopy were then used to investigate the mechanical properties, curing networks, and hydrogen bonding (H-bonds) of these binders. Additionally, a novel method based on the molecular theory of elasticity and the statistical theory of rubber elasticity was used to analyze the integrity of the networks. The results showed that the curing parameter R strongly influences the mechanical properties and toughness of the binders, and that a tensile stress (σm) of 1.6 MPa and an elongation (εm) of 1041% was observed with an R value of 1.6. The cross-linking density increased sharply with the curing parameter, but only modestly with an R value ≥ 1.8. The proportion of H-bonds formed by the imino groups increased with the R value and reached 72.61% at an R value of 1.6, indicating a positive correlation between the H-bonds and σm. Molecular entanglement was demonstrated to increase with R and to contribute dramatically to the mechanical performance. The integrity of these networks, evaluated by a correction factor (A), varies with R, and a network of the GAP/TDI binder with an R value of 1.6 is desirable.

4

The Preparation of NC Microspheres and BuNENA Modified NC Microspheres by the Breath Figures Method

He L., He W., Luo Y.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 3

567--578

EN

The ‘breath figures’ method was used to prepare nitrocellulose (NC) microspheres and N-butyl-N-(2-nitroxyethyl)nitramine (BuNENA) modified NC microspheres (BMNM). By using acetone as the solvent and non-solvent n-hexane as the atmosphere, NC microspheres and BMNM were obtained. The matching of solvents and non-solvents was the key factor influencing the final morphology. TG and DSC were employed to study the thermal decomposition characteristics of BMNM. The results suggested that there were two distinct stages of thermal mass loss from the BMNM: the first was the mass loss associated with partial volatilisation of BuNENA, and its activation energy was 68.54 kJ/mol. The second mass loss was the thermal decomposition of NC and residual BuNENA with a high activation energy (249.53 kJ/mol, calculated by the Kissinger method). According to the thermal decomposition kinetics model, the optimal kinetics model of BMNM was B1-A2. The addition of BuNENA did not influence the thermal decomposition of NC.

5

Measurement of the Indentation Modulus and the Local Internal Friction in Amorphous SiO2 Using Atomic Force Acoustic Microscopy

Zhang B., Wagner H., Büchsenschütz-Göbeler M., Luo Y., Küchemann S., Arnold W., Samwer K.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 1

9--12

EN

For the past two decades, atomic force acoustic microscopy (AFAM), an advanced scanning probe microscopy technique, has played a promising role in materials characterization with a good lateral resolution at micro/nano dimensions. AFAM is based on inducing out-of-plane vibrations in the specimen, which are generated by an ultrasonic transducer. The vibrations are sensed by the AFM cantilever when its tip is in contact with the material under test. From the cantilver’s contactresonance spectra, one determines the real and the imaginary part of the contact stiffness k*, and then from these two quantities the local indentation modulus M' and the local damping factor Qloc-1 can be obtained with a spatial resolution of less than 10 nm. Here, we present measured data of M' and of Qloc-1 for the insulating amorphous material, a-SiO2. The amorphous SiO2 layer was prepared on a crystalline Si wafer by means of thermal oxidation. There is a spatial distribution of the indentation modulus M' and of the internal friction Qloc-1. This is a consequence of the potential energy landscape for amorphous materials.

6

Multivariate information dynamic monitoring system application of tunnel construction process model test

Liu Q., Chen J., Wei L., Huang P., Luo Y., Pu X.

Archives of Civil Engineering

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2016

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Vol. 62, nr 3

117--136

EN

Geomechnical model testing has been widely applied as a kind of research technique in underground engineering problems. However, during the practical application process, due to the influence of many factors, the desired results cannot be obtained. In order to solve this problem, based on the measurement requirements of the model test, combined with FBG(Fiber Bragg Grating) sensor technology and traditional measurement methods, an FBG monitoring system, Micro-multi-point displacement test system, resistance strain test system and surrounding rock pressure monitoring system are developed. Applying the systems to a model test of the tunnel construction process, the displacement in advance laws of tunnel face, radial displacement distribution laws and surrounding rock pressure laws are obtained. Test results show that a multivariate information monitoring system has the advantage of high precision, stability and strong anti-jamming capability. It lays a solid foundation for the real-time data monitoring of the tunnel construction process model test.

PL

Niniejsza praca omawia system dynamicznego monitorowania wieloczynnikowej informacji podczas badania modelu procesu budowy tunelu. Geometryczna metoda badania modelu jest skuteczną metodą badania poważnych problemów geotechnicznych, które wiążą się ze stosowaniem podobnych materiałów w pomieszczeniu, tworzeniem podobnych modeli na podstawie podobnych zasad oraz opierają się na obserwacji naprężeń, odkształceń i przemieszczeń wielowymiarowej informacji, w celu zrozumienia zjawiska mechanicznego i prawa stanu naprężeń i przemieszczeń na prototypie, aby osiągnąć cel realizacji geotechnicznego projektowania i budowy. Z uwagi na praktyczne, zaawansowane przemieszczenie w przedniej części tunelu oraz przemieszczenie samej powierzchni tunelu, pomiary są trudne do przeprowadzenia za pośrednictwem monitorowania. Możemy prowadzić skuteczną analizę i dyskusję dotyczącą słabej/uszkodzonej skały otaczającej przy użyciu podobnej geometrycznej metody badania modelu. Jednakże, badania modelu zależą od wielu czynników w rzeczywistym procesie zastosowania, przez co trudno jest osiągnąć pożądany efekt. Wśród nich, technologia pozyskiwania licznych informacji na temat dynamicznego monitorowania procesu badania stała się ważnym czynnikiem, ograniczającym rozwój geometrycznej metody badań modelu. Jak wiemy, mnogość informacji geometrycznej na temat metody badań modelu obejmuje napięcie, naprężenie, ciśnienie, przemieszczenie, itp. Mnogość informacji w procesie budowy tunelu, takich jak dynamiczne monitorowanie pierwszego przemieszczenia, przemieszczenie i tylne przemieszczenie powierzchni tunelu, jest rzadko analizowana. Jednakże, pomyślne zdobycie licznych informacji podczas budowy tunelu jest kluczem do sukcesu w badaniu modelu. Dlatego też, w celu zbadania systemu monitorowania wielu informacji w procesie budowy tunelu, należy uchwycić stan przekształcenia i naprężenia, jak również zwiększyć dokładność pomiarów i nie ma wątpliwości co do pełnego wykorzystania zalet technologii badań modelu. Na podstawie techniki monitorowania światłowodu, różnorodny zbiór informacji dla systemu monitorowania jest tworzony jako rdzeń systemu dynamicznego monitorowania światłowodu w czasie rzeczywistym. W połączeniu z wysokoprecyzyjnym mechanicznym i mikroprzemieszczającym miernikiem o typie kraty i innymi środkami, zgodnie z wymogami pomiarów badania modelu, system monitorowania licznych informacji został opracowany i skutecznie wykorzystany w procesie budowy tunelu. Wyniki badania modelu pokazują, że system może być stosowany do monitorowania procesu budowy tunelu, a ponadto jest zdolny do wychwytywania drobnych zmian i wartości fluktuacji komunikatów wielojednostkowych, jak również do tworzenia podwaliny dla powodzenia badania modelu.

7

Detection of multilayer cavities by employing RC-DTH air hammer system and cavity auto scanning laser system

Luo Y., Li L., Peng J., Yin K., Li P., Gan X., Zhao L., Su W.

Archives of Mining Sciences

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2015

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Vol. 60, no. 4

1041--1052

EN

The subterranean cavities are seriously threatened to construction and mining safety, and it’s important to obtain the exact localization and dimensions of subterranean cavities for the planning of geotechnical and mining activities. Geophysical investigation is an alternative method for cavity detection, but it usually failed for the uncertainly solution of information and data obtained by Geophysical methods. Drilling is considered as the most accurate method for cavity detection. However, the conventional drilling methods can only be used for single cavity detection, and there is no effective solution for multilayer cavities detection have been reported. In this paper, a reverse circulation (RC) down-the-hole (DTH) air hammer system with a special structured drill bit is built and a cavity auto scanning laser system based on laser range finding technique was employed to confirm the localization and dimensions of the cavities. This RC-DTH air hammer system allows drilling through the upper cavities and putting the cavity auto scanning laser system into the cavity area through the central passage of the drill tools to protect the detection system from collapsing of borehole wall. The RC-DTH air hammer system was built, and field tests were conducted in Lanxian County Iron Ore District, which is located in Lv Liang city of Shan Xi province, the northwest of china. Field tests show that employing the RC-DTH air hammer system assisted by the cavity auto scanning laser system is an efficiency method to detect multilayer cavities.

PL

Podziemne wgłębienia i pustki stanowią poważne zagrożenie dla budowli oraz dla działalności górniczej; dlatego też podstawowym zagadnieniem jest ich dokładna lokalizacja i określenie wymiarów. Jest to niezbędne dla planowania prac geotechnicznych i wydobywczych. Badania geofizyczne są alternatywną metodą wykrywania podziemnych zagłębień, zazwyczaj jednak okazują się nieskuteczne ze względu na niepewność rozwiązań oraz danych uzyskiwanych za pomocą metod geofizycznych. Wykonanie odwiertu jest najdokładniejszą metodą wykrywania zagłębień i pustek, jednakże konwencjonalne metody prowadzenia wierceń pozwalają na wykrycie jednego tylko zagłębienia, nie ma też skutecznego rozwiązania kwestii istnienia zagłębień i pustek przechodzących przez liczne warstwy górotworu. W pracy omówiono zastosowanie układu młota pneumatycznego wgłębnego z odwrotnym obiegiem płuczki, wyposażonego w odpowiednie urządzenie wiertnicze, oraz układu skanera laserowego wykorzystującego technikę dalmierza do potwierdzania lokalizacji pustek i ich wymiarów. Prezentowany młot umożliwia dokonanie odwiertu w zagłębieniach i pustkach znajdujących się w warstwach wierzchnich, następnie w zagłębieniu tym umieszczane jest laserowe urządzenie skanujące powierzchnię komory wprowadzane poprzez główny kanał w urządzeniu wiertniczym, tak by zabezpieczyć skaner na wypadek osunięcia się ścian otworu. Układ składający się z młota pneumatycznego zbudowano i przetestowano w warunkach polowych w zagłębiu miedziowym w okręgu Lanxian, w pobliżu miasta LV Liang w prowincji Shan Xi, w północno-zachodnich Chinach. Badania przeprowadzone w terenie wykazały, że zastosowanie układu złożonego z młota pneumatycznego wgłębnego RC-DTH wraz z laserowym skanerem jest skuteczną metodą wykrywania pustek przechodzących przez liczne warstwy.

8

Modeling atmosphere composition and determining explosibility in a sealed coal mine volume

Cheng J., Luo Y.

Archives of Mining Sciences

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2014

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Vol. 59, no. 1

25--40

EN

Explosions originated from or around the sealed areas in underground coal mines present a serious safety threat. The explosibility of the mine atmosphere depends on the composition of oxygen, combustible and inert gases. In additional, the composition in the inaccessible sealed areas change with time under various factors, such as gases emissions, air leakage, inert gases injected, etc. In order to improve mine safety, in this paper, a mathematical model based on the control volume approach to simulate the atmosphere compositions is developed, and the expanded Coward explosibility triangle diagram is used to assess the mine gas explosion risk. A computer program is developed to carry out the required computations and to display the results. In addition, the USBM explosibility diagram is also included in the program to serve as a double check.

PL

Wybuchy powstające wewnątrz lub wokół zamkniętych (odizolowanych) regionów w podziemnych kopalniach węgla stanowią poważne zagrożenie. Możliwość wystąpienia wybuchu powietrza kopalnianego uzależniona jest od proporcji zawartego w nim tlenu, gazów palnych i gazów obojętnych. Ponadto, skład atmosfery wewnątrz zamkniętych odizolowanych przestrzeni ulega zmianom w czasie pod wpływem różnorakich czynników: wydzielanie gazów, przecieki powietrza, doprowadzanie gazów obojętnych. Dla poprawy bezpieczeństwa pracy w kopalni opracowano model matematyczny bazujący na metodzie objętości kontrolnej dla symulacji składu powietrza. Rozszerzony wykres Cowarda wskazujący skłonność do wybuchu wykorzystany został do oszacowania ryzyka wystąpienia wybuchu gazów kopalnianych. Opracowano program komputerowy który wykonuje niezbędne obliczenia i wyświetla wyniki. Ponadto, dla dodatkowego potwierdzenia wyników wykorzystano wykres USBM obrazujący niebezpieczeństwo wybuchu.

9

The experiment of convergence property for circuit layout demonstrates the defect in evolutionary mechanism

Luo Y.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 3b

47--49

EN

In the current recognized evolutionary mechanism, an elementary fact has always been ignored: a predominant trait can come from the relationship of diverse characters, besides the quantity of a single character. This research has designed a series of experiments of simulation for circuit layout to test whether the current recognized evolutionary mechanism is effective for the predominant trait from relationships. The results of these experiments demonstrate the defect in the current recognized evolutionary mechanism, which cannot account for the heritable predominant traits from relationships.

PL

W artykule przedstawiono serię eksperymentów, symulujących przy pomocy układu scalonego współczesny mechanizm ewolucyjny, pod kątem jego efektywności w przypadku pochodzenia cech dominujących. Wyniki badań wskazują błędne podejście w obecnie znanym mechanizmie ewolucyjnym, nie biorące pod uwagę dziedziczenia głównych cech w wyniku powiązania innych.

10

An Online Monitoring System of Corona Loss of High Voltage Transmission Lines Based on Metalized Membrane Method

Luo Y., Liu H., Wang M., Xin X., Zhang Y., Li R., Wang G., Wu J., Bai X.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 10

217-220

EN

An online monitoring system of corona loss of high voltage transmission lines based on metalized membrane method is developed in this paper. The system includes 3 components: the upper computer, the conductor voltage acquisition module and the corona leakage current acquisition module. The corona leakage current acquisition module is set on the high voltage line. The transmission line is covered by a certain length of thin metalized membrane . The sampling resistance is put paralleling between metal layer and bundle conductor. The conductor voltage acquisition module is set in transformer substation. The two modules are synchronized by the rising edge of Pulse Per Second (PPS) emitted by Global Position System (GPS), and the data is sent to the public port of mobile telephone network by General Packet Radio Service (GPRS). The remote upper computer gets the data and calculates corona loss of each bundle conductor by visiting public port. The experiment results show that the system can monitor the corona loss accurately. The whole study is helpful in the further research of UHV transmission line’s corona in different environment and weather.

PL

Zaprezentowano metodę monitorowania strat powodowanych ulotem (wyładowaniem koronowym) w liniach transmisyjnych wysokiego napięcia. Do tego celu wykorzystano metalizowaną membranę. Układ składa się z trzech modułów: komputera, systemu akwizycji napia) ęcia i systemu akwizycji prądu ulotu. Linia transmisyjna jest pokryta na pewnej długości cienką metalizowaną membraną. Do lokalizacji ulotu zastosowano moduł GPS a do transmisji danych moduł GPRS.

11

A Complete Model for Iron Losses Prediction in Electric Machines Including Material Measurement, Data Fitting, FE Computation and Experimental Validation

Zhao H., Luo Y., Ren W., Peter B.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5b

52-55

EN

This paper presents a complete model & process for predicting the iron losses in electric machines. The method includes material measurement, data fitting for loss coefficient determination, FE computation and experimental validation. The model is based on the loss separation of hysteresis and eddy-current losses. Also a least squares based method of curve fitting, to obtain material loss coefficients for FE analysis, is derived from the tested specific core losses of a steel lamination ring sample. The generality of the completed method is further verified b application to different steel types and electric machines. The results predicted by the model show excellent agreement with the tested data for a high speed PM DC motor and a PM BLDC motor.

PL

Zaprezentowano metodę przewidywania strat w maszynach elektrycznych uwzględniając właściwości materiałowe, współczynniki strat, obliczenia numeryczne i weryfikację eksperymentalną.

12

Leaf nitrogen resorption pattern along habitats of semi-arid sandy land with different nitrogen status

Luo Y., Zhao X., Zuo X., Zhang J., Liu R., Wang S.

Polish Journal of Ecology

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2010

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Vol. 58, nr 4

707-716

EN

To assess nitrogen (N) resorption patterns in semi-arid sandy land, N concentrations in green leaves (N[g]) and senesced leaves (N[s]) of 35 species of shrubs and herbages were measured along habitats of decreasing soil total N (0.54 to 0.041 g g[^-1] d.w. of top soil level) in Horqin Sandy Land (Inner Mongolia, China). These habitats are following: inter-dune grassland (IDG), fixed sand dune (FD), semi-fixed sand dune (SFD), semi-mobile sand dune (SMD), and mobile sand dune (MD) were considered. Results showed that Ng and Ns (i.e. nitrogen resorption proficiency, NRP) increased and leaf nitrogen use efficiency (NUE) decreased significantly with increasing soil N status across the above habitas, but nitrogen resorption efficiency (NRE) was not affected. The levels of N[g], N[s] and NUE experience two stages across habitats: first, there were low N[g] and N[s and high NUE in MD and SMD; second, there were high N[g] and N[s] and low NUE in IDG, FD and SFD. Plants from IDG, FD and SFD had incomplete N resorption during foliar senescence, but plants from MD and SMD had complete N resorption. Leaf NRE was determined by life forms which had no significant effect on N[g] but on N[s] and NUE. For all plants in the five habitats, NRE and NUE decreased with the sequence of grass, herb, shrub, while Ns showed a contrary tendency. Plants from strong N limitation habitats did not show higher NRE, but showed higher NRP and leaf NUE, so NRP was a more sensitive indicator of changes in N status than NRE. In conclusion, Leaf N resorption patterns were mainly determined by soil N status across habitats, and there were some consistent patterns among life forms.

13

Relationship between seed size and plant abundance in an alpine meadow of the Qinghai-Tibetan Plateau

Liu B., Luo Y.

Polish Journal of Ecology

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2009

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Vol. 57, nr 3

573-579

EN

Theoretical and field studies on seed size and plant abundance relationship have been conducted in various communities. However, inconsistent patterns have emerged from these studies, and still little is known about alpine meadows. Here we identified four models and their predictions: the seed size/number trade-off model (SSNTM), the succession model (SM), the spatial competition model (SCM), and the triangle model (TM), in order to assess the relationship between seed size and abundance in alpine meadows, and to elucidate underlying mechanisms. The study site was situated on the eastern Qinghai-Tibetan Plateau at 3500 m above sea level. From 1999 through 2001, two indices of plant abundance (aboveground biomass and density) were simultaneously measured in 45 quadrates (0.25 m[^2]). Data for 101 plant species (mostly Cyperaceae, Poaceae, Asteraceae, Ranunculaceae and forbs) showed that seed size is like log normal distributed, and it slightly skewed in smaller-sized seeds. The SSNTM, the TM, the SM and the SCM models were not supported in this alpine meadow, and the relationship between seed size and abundance was always positive (although in some samples, the relationship was not significant). The positive correlation between seed size and abundance observed for some grassland communities was also demonstrated in the alpine meadow. It suggests that seed size depends on the plant growth form, but the biomass-density relationship is inconsistent with previous studies. This suggests that the measure of abundance used in these studies is not the only reason for inconsistency of seed size.

14

Synchrotron microanalytical methods in the study of trace and minor elements in apatite

Rakovan J., Luo Y., Borkiewicz O.

Mineralogia

|

2008

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Vol. 39, iss. 1/2

31--40

EN

Synchrotron X-ray facilities have the capability for numerous microanalytical methods with spatial resolutions in the micron to submicron range and sensitivities as low as ppm to ppb. These capabilities are the result of a high X-ray brilliance (many orders of magnitude greater than standard tube and rotating anode sources); a continuous, or white, spectrum through the hard X-ray region; high degrees of X-ray columniation and polarization; and new developments in X-ray focusing methods. The high photon flux and pulsed nature of the source also allow for rapid data collection and high temporal resolution in certain experiments. Of particular interest to geoscientists are X-ray fluorescence microprobes which allow for numerous analytical techniques including X-ray fluorescence (XRF) analysis of trace element concentrations and distributions; X-ray absorption spectroscopy (XAS) for chemical speciation, structural and oxidation state information; X-ray diffraction (XRD) for phase identification; and fluorescence microtomography (CMT) for mapping the internal structure of porous or composite materials as well as elemental distributions (Newville et al. 1999; Sutton et al. 2002; Sutton et al. 2004). We have employed several synchrotron based microanalytical methods including XRF, microEXAFS (Extended X-ray Absorption Fine Structure), microXANES (X-ray Absorption Near Edge Structure) and CMT for the study of minor and trace elements in apatite (and other minerals). We have also been conducting time resolved X-ray diffraction to study nucleation of and phase transformations among precursor phases in the formation of apatite from solution at earth surface conditions. Summaries of these studies are given to exemplify the capabilities of synchrotron microanalytical techniques.

15

Tensile and tearing properties of bi-axial warp knitted coated fabrics

Luo Y., Hong H., Fangueiro R.

Autex Research Journal

|

2008

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Vol. 8, no. 1

17--20

EN

Based on uni-axial tensile testing, the performances of bi-axial warp knitted PET/PVC flexible composites has been analyzed in seven in-plane directions, i.e., 0°,15°,30°,45°,60°,75° and 90°. The crack propagation of each sample has been observed and analyzed by evaluating the influence of the crack length and direction under uni-axial testing. The results show that bi-axial warp knitted coated fabrics present a strong orthotropic behavior and that the tearing strength depends on the initial crack orientation and length. Regardless of the crack length and orientation, the propagation is always perpendicular to the tensile loading direction.

16

Hydroxylation of Alkanes Using H2O2 or tert-BuOOH Catalyzed by Silica-based Fe(III) Interphase Catalysts

Luo Y., Zhang L., Zong M., Ménage S., Fontecave M.

Polish Journal of Chemistry

|

2006

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Vol. 80, nr 8

1407-1414

EN

Two novel silica-based organic-inorganic hybrid (interphase) Fe(III) catalysts have been successfully prepared by the flexible ligandmethod, characterized and applied to the efficient catalytic oxidation of various types of substrates using 30% H2O2 or tert-BuOOH under mild conditions. The catalysts can be recovered and reused for four reaction cycles with total turnover numbers being about 29 using cyclohexene as the substrate. The mechanism for the O-O bond cleavage was proposed based on the results in combination with previous experimental results.