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1

The Effects of Epoxidized Acrylated Castor Oil (EACO) on Soft Poly (vinyl chloride) Films as a Main Plasticizer

Song F., Xia H., Jia P., Zhang M., Hu L., Zhou Y.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 4

13--19

EN

In this work, an environmentally friendly type plasticizer was introduced. The synthesis consisted of two steps. In the first step, castor oil (CO) was acrylated and then the acrylated castor oil (ACO) was epoxidized with the presence of formic acid and hydrogen peroxide in the second step. The epoxidized acrylated castor oil (EACO) was characterized by FTIR and 1H-NMR techniques. The EACO was used as a main plasticizer to obtain plasticized PVC materials and compared with DOP. The results showed that EACO improved polyvinyl-chloride (PVC) plasticization performance and reduced Tg from 81.06°C to 1.40°C. Plasticized PVC materials with EACO showed similar mechanical properties and better thermal stability than DOP. EACO had better volatility stabilities, migration and solvent extraction in PVC than DOP. EACO can be used to replace DOP to prepare soft films.

2

Effect of activated carbon on methomyl poisoning by urine metabolomics base on gas chromatography–mass spectrometry

Li L., Hu L., Chen B., Dong Y., Lin Z., Wang Z., Wen C., Wang X., Wang S.

Acta Chromatographica

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2018

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Vol. 30, no. 1

21--25

EN

In this study, we developed a urine metabolomic method by gas chromatography–mass spectrometry (GC–MS) combination with biomedical results to evaluate the effect of activated carbon on methomyl poisoning rats. The rats were divided into four groups, methomyl group, two activated carbon treatment group, and control group. According to the biochemical results, it indicated that activated carbon treated rats could cause liver and kidney function changes. According to the urine metabolomics results, activated carbon treatment group (10 min) and activated carbon treatment group (30 min) could be distinguished from methomyl group, and activated carbon treatment group (10 min) could be separated from activated carbon treatment group (30 min) rats, which indicated that the treatment of rats by activated carbon in different time had a different effect. The results indicate that metabolomic method by GC–MS may be useful to elucidate activated carbon treated on methomyl poisoning rats.

3

Development and validation of UPLC–MS/MS method for determination of eupatilin in rat plasma and its application in a pharmacokinetics study

Geng P., Luo X., Peng X., Lin Z., Chen W., Zhang J., Wen C., Hu L., Hu S.

Acta Chromatographica

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2018

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Vol. 30, no. 4

231--235

EN

Eupatilin, mainly derived from Artemisia asiatica (Asteraceae), is an O-methylated flavone with various bioactivities. In the present study, a validated ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was established for the quantification of eupatilin in rat plasma with the internal standard (IS) of tussilagone and the protein precipitation of plasma samples was performed using acetonitrile–methanol (9:1, v/v). The eupatilin and IS were eluted separately on a UPLC BEH C18 column (2.1 mm × 100 mm, 1.7 μm) with the gradient mobile phase consisted of 0.1% formic acid and acetonitrile. The protonated analytes were quantified by multiple reactions monitoring (MRM) mode with an electrospray ionization (ESI) source operated in positive ion mode. The calibration plots were found to be linear over the range from 2 to 1000 ng/mL for eupatilin in rat plasma. Both of the intra-day and inter-day precision variations (RSDs) were ≤13%. The recoveries of eupatilin in rat plasma were between 83.7% and 94.6%, and the accuracy of the method ranged from 95.8% to 107.6%. In addition, the validated method was applied to pharmacokinetic study of eupatilin after an intravenous dose of 2 mg/kg to rats.

4

Different Patterns of Changes in Foliar Carbon Isotope Composition Along Altitude

He Z., Zhan S., Wang W., Hu L., Wu S.

Polish Journal of Ecology

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2017

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Vol. 65, nr 2

227--235

EN

Three types of alpine plant species, Carex montis-everestii, Quercus aquifolioides and Stipa capillacea, along an altitudinal gradient of 3005-5025 m on the Tibetan Plateau, were chosen to test the generality of the hypothesis that foliar carbon isotope composition (δ13C) of C3 plants increases significantly with altitude and to determine climate drivers shaping its altitudinal pattern. Temperature and relative humidity showed significantly negative correlations with altitude; however, precipitation and soil water potential remained unchanged with altitude. Foliar δ13C of C. montis-everestii, Q. aquifolioides, S. capillacea alone or combined together did not significantly increase with altitude, which does not support the leading hypothesis of increased foliar δ13C with altitude. There was no difference in foliar δ13C among all three species. Multi-factor correlation analyses showed that temperature, precipitation and relative humidity alone did not affect foliar δ13C of C. montis-everestii and S. capillacea, but conferred significant effects on foliar δ13C of Q. aquifolioides.

5

Self-Plasticization of PVC via click reaction of a monooctyl phthalate derivative

Jia P., Wang R., Hu L., Zhang M., Zhou Y.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 3

16--19

EN

Modified PVC (M-PVC) material with suppressed migration and low glass transition temperature was prepared via click reaction of a monooctyl phthalate derivative. Chemical structure and composition of M-PVC were characterized by FT-IR, 1H NMR and element analysis. Thermal stability, glass transition temperature and migration stability of M-PVC were studied with TGA, DSC and migration tests, respectively. The study showed that M-PVC exhibited poor thermal stability, and low glass transition temperature of 66.0°C. No migration was found in distilled water, 10% (v/v) ethanol, 30% (w/v)acetic acid and petroleum ether. The PVC material is expected to preparing PVC products in the areas with high migration resistance requirement.

6

Fuzzy Availability Assessment for Discrete Time Multi-State System under Minor Failures and Repairs by Using Fuzzy Lz -transform

Hu L., Zhang Z., SU P., Peng R.

Eksploatacja i Niezawodność

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2017

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Vol. 19, no. 2

179--190

PL

W niniejszej pracy badano metodę oceny dynamicznej, rozmytej gotowości eksploatacyjnej (dostępności) dyskretnego w czasie systemu wielostanowego pracującego w trybie drobnych uszkodzeń i napraw. Tradycyjnie zwykło się zakładać, że analiza niezawodności dostarcza dokładnych danych niezawodnościowych na temat danego dyskretnego w czasie komponentu/systemu. W praktyce inżynieryjnej jednak trudno jest uzyskać dokładne dane do oceny właściwości komponentu/systemu. W niniejszej pracy zaproponowano jak problem ten można rozwiązać wykorzystując do oceny dynamicznej gotowości dyskretnego w czasie systemu wielostanowego, teorię zbiorów rozmytych. Rozmyty model Markowa z dyskretnym czasem i rozmytą macierzą prawdopodobieństw przejść zastosowano do analizy rozmytego prawdopodobieństwa stanu każdego elementu w dowolnym czasie dyskretnym. Opracowano rozmytą transformatę Lz rozmytego, dyskretnego w stanach i czasie łańcucha Markowa, która pozwala poszerzyć transformatę Lz modelu Markowa dyskretnego w stanach i ciągłego w czasie o zbiory ostre. W oparciu o metodę alfa przekrojów oraz rozmytą transformatę Lz, obliczono dynamiczną rozmytą gotowość eksploatacyjną systemu, wykorzystując do tego celu technikę programowania parametrycznego. Zastosowanie proponowanej metody zilustrowano na przykładzie liczbowym analizując układ przesyłu.

EN

This paper studies assessment approach of dynamic fuzzy availability for a discrete time multi-state system under minor failures and repairs. Traditionally, it was assumed that the exact reliability data of a component/system with discrete time are given in reliability analysis. In practical engineering, it is difficult to obtain precise data to evaluate the characteristics of a component/system. To overcome the problem, fuzzy set theory is employed to deal with dynamic availability assessment for a discrete time multi-state system in this paper. A fuzzy discrete time Markov model with fuzzy transition probability matrix is proposed to analyze the fuzzy state probability of each component at any discrete time. The fuzzy Lz-transform of the discrete-state discrete-time fuzzy Markov chain is developed to extend the Lz-transform of the discrete-state continuous-time Markov model with crisp sets. Based on the α-cut approach and the fuzzy Lz-transform, the dynamic fuzzy availability of the system is computed by using parametric programming technique. To illustrate the proposed method, a flow transmission system is analyzed as a numerical example.

7

Fault diagnosis for complex systems based on dynamic evidential network and multi-attribute decision making with interval numbers

Duan R., Hu L., Lin Y.

Eksploatacja i Niezawodność

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2017

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Vol. 19, no. 4

580--589

EN

The complexity of modern system structures and failure mechanisms makes it very difficult to locate the system fault. It has characteristics of dynamics of failure, diversity of distribution and epistemic uncertainties, which increase the challenges in the fault diagnosis significantly. This paper presents a fault diagnosis framework for complex systems within which the failure rates of components are expressed in interval numbers. Specifically, it uses a dynamic fault tree (DFT) to model the dynamic fault behaviors and deals with the epistemic uncertainties using Dempster-Shafer (D-S) theory and interval numbers. Furthermore, a solution is proposed to map a DFT into a dynamic evidential network (DEN) to calculate the reliability parameters. Additionally, diagnostic importance factor (DIF), Birnbaum importance measure (BIM) and heuristic information values (HIV) are taken into account comprehensively in order to obtain the best fault search scheme using an improved VIKOR algorithm. Finally, an illustrative example is given to demonstrate the efficiency of this method.

PL

Złożoność nowoczesnych struktur systemowych oraz mechanizmów uszkodzeń powoduje trudności w lokalizacji uszkodzeń systemu. Systemy złożone charakteryzują się cechami, takimi jak dynamika uszkodzeń, różnorodność rozkładów oraz niepewność epistemiczna, które czynią wyzwania dotyczące diagnostyki uszkodzeń znacznie trudniejszymi. W niniejszym artykule przedstawiono metodę diagnozowania uszkodzeń systemów złożonych, w której intensywność uszkodzeń poszczególnych składników wyraża się za pomocą liczb przedziałowych. W szczególności, podejście to wykorzystuje dynamiczne drzewo błędów (DFT) do modelowania dynamicznych zachowań związanych z uszkodzeniami oraz rozwiązuje problem niepewności epistemicznej przy użyciu teorii Dempstera-Shafera (DS) oraz liczb przedziałowych. W celu obliczenia parametrów niezawodności, zaproponowano rozwiązanie polegające na odwzorowaniu DFT w dynamiczną sieć dowodową (DEN). Dodatkowo, w sposób kompleksowy wykorzystano czynnik ważności diagnostycznej (DIF), miarę ważności Birnbauma (BIM) oraz wartości informacji heurystycznej (HIV), aby przy użyciu udoskonalonego algorytmu VIKOR uzyskać najlepszy system wyszukiwania błędów. Skuteczność omawianej metody zilustrowano na podstawie przykładu.

8

A new simulation-optimization approach for the circulation facilities design at urban rail transit station

Khattak A., Jiang Y., Zhu J., Hu L.

Archives of Transport

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2017

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Vol. 43, iss. 3

69--90

EN

Width design of the urban rail transit stations circulation facilities is a vital issue. The existing width design approach failed in fully considering the essential factors such as fluctuation in passengers’ arrival process, fluctuation and state-dependence in passengers walking speed and the blocking when passengers’ demand exceeds the capacity of facilities. For this purpose, a PH-based simulation-optimization approach is proposed that fully considers the fluctuation, the state-dependence, Level of Service (LOS) and blocking effect. This novel approach provides automatic reconfiguration of the widths of circulation facilities by a concurrent implementation of a PH-based Discrete-Event Simulation (DES) model and the Genetic Algorithm (GA). The proposed PH-based simulation-optimization approach and the existing design approaches based on the exponential and deterministic models are applied to design the widths of circulation facilities. The results reveal that the circulation facilities designed by the proposed approach have larger widths. Similarly, increase in the SCV of arrival interval results in increasing the widths designed by the proposed approach increase while the widths of the other two approaches stay the same. The width designed of the proposed approach increase at faster rate than that of the other two approach when the passengers’ arrival rate increases.

9

Fault risk assessment of underwater vehicle steering system based on virtual prototyping and Monte Carlo simulation

He D., Hu N., Hu L., Chen L., Guo Y., Chen S.

Polish Maritime Research

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2016

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nr 3

97--105

EN

Assessing the risks of steering system faults in underwater vehicles is a human-machine-environment (HME) systematic safety field that studies faults in the steering system itself, the driver’s human reliability (HR) and various environmental conditions. This paper proposed a fault risk assessment method for an underwater vehicle steering system based on virtual prototyping and Monte Carlo simulation. A virtual steering system prototype was established and validated to rectify a lack of historic fault data. Fault injection and simulation were conducted to acquire fault simulation data. A Monte Carlo simulation was adopted that integrated randomness due to the human operator and environment. Randomness and uncertainty of the human, machine and environment were integrated in the method to obtain a probabilistic risk indicator. To verify the proposed method, a case of stuck rudder fault (SRF) risk assessment was studied. This method may provide a novel solution for fault risk assessment of a vehicle or other general HME system.

10

A novel biobased polyester plasticizer prepared from palm oil and its plasticizing effect on poly (vinyl chloride)

Jia P., Zhang M., Hu L., Zhou Y.

Polish Journal of Chemical Technology

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2016

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Vol. 18, nr 1

9--14

EN

In this study, palm oil was the first time to convert into a novel polyester plasticizer for polyvinyl chloride (PVC). In the first stage, palm oil was converted into palm oil monoglyceride (POM) by alcoholysis with glycerol. Next, a novel palm oil monoglycerides based polyester plasticizer (POMP) was synthesized from POM and maleic anhydride through esterification and condensation reaction. The structure of POMP was characterized with FTIR, 1H NMR and GPC. Then PVC blends were prepared using POMP as a plasticizer, melting behavior, thermal property, compatibility, mechanical properties and mechanism of plasticization of PVC blends were systematically studied. Melting behavior indicated that POMP could decrease the torque and the melt viscosity of PVC blends that was conducive to process. With the content of POMP increasing from 5 g to 15 g in PVC blends, the plasticized PVC blends demonstrated better compatibility, the degradation temperature (Td) increased from 252.6°C to 257.0°C, the glass transition temperature (Tg) decreased from 55°C to 49.5°C. Plasticization was put into effect by interaction of the electron cloud between the PVC chain and POMP molecule. This study may lead to the development of new type of PVC plasticizer based on vegetable oil.

11

The plasticizing effect of properties of manganous chloride and glycerin on poly(vinyl alcohol)

Jia P., Zhang M., Bo C., Hu L., Zhou Y.

Polish Journal of Chemical Technology

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2015

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Vol. 17, nr 2

29--33

EN

Poly(vinyl alcohol) films were prepared with manganous chloride (MnCl2 · 4H2O) and glycerin as complex plasticizer. The micro morphology of pure PVA film and complex plasticizer plasticized PVA films was observed by scanning electron microscope (SEM). The interaction between complex plasticizer and PVA molecules was investigated by Fourier transform infrared spectroscopy (FT-IR). The influence of complex plasticizer on crystalline, thermal and mechanical properties of PVA films was studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), and tensile testing, respectively. The results showed that the complex plasticizer of MnCl2 · 4H2O/glycerin could interacted with PVA molecular and then effectively destroy the crystals of PVA. PVA films plasticized with complex plasticizer of MnCl2 · 4H2O/glycerin became soft and ductile, with lower tensile strength and higher elongation at break compared with PVA films. This is an important cause of plasticization of the complex plasticizer of MnCl2 · 4H2O/glycerin on PVA films.

12

Study on the Initiation Capacities of Conical Ring Booster Pellets

Hu L., Hu S., Cao X., Li J.

Central European Journal of Energetic Materials

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2014

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Vol. 11, no. 3

335--348

EN

The insensitive main charge explosive is becoming an important part of modern weapon development. Insensitive main charge explosives generally have a high critical initiation pressure. The detonation pressure of a traditional cylindrical booster pellet is constant at a specific density and consequently has insufficient energy output to reliably initiate an insensitive main charge explosive. To ensure that this requirement could be achieved, the conical ring booster pellet was designed and optimized. Eight-point-synchronous explosive circuits were designed as appropriate to the sizes of the four booster pellets. The initiation processes of the four conical booster pellets equipped with the eight-point circuit were simulated using ANSYS/LY-DYNA software. The experimental measurements were performed in order to test the initiation capacities of these conical booster pellets. The results demonstrated that their initiation capacities are much better than the initiation capacity of a cylindrical booster pellet. The optimum size of the conical ring booster pellet is when the ratio of the inner to the upper diameter is 0.52, the ratio of the inner to the lower diameter is 0.44, and the ratio of the height to the lower diameter is 0.50.

13

Morphological responses of six plant species to patchy habitat with different nitrogen concentrations using in-growth core methods

Du F., Sui Y., Xu X., Zhang X., Hao W., Shao M., Hu L., Shan L.

Polish Journal of Ecology

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2013

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Vol. 61, nr 2

257--269

EN

Soil nutrient pattern can be a functional tool for grassland restoration. In order to promote the growth of a specific or group of expected plant species, it is necessary to measure the responses of different species to nutrient – rich patches and detect the differences among them. In this article, we measured aboveground biomass and morphological traits of six species as dry weight, length, surface area, specific root length and diameter of fine roots in response to nitrogen addition patches using ingrowth core method. The six species are Artemisia scoparia, Stipa bungeana, Artemisia sacrorum, Artemisia giraldii, Lespedeza dahurica and Astragalus melilotoides. All are the dominant species in different stages of secondary succession of loess hilly region, China. Twelve individuals of each species were selected to install ingrowth cores. Six of the individuals were used as treatment group, they were treated to install with four cores of no (addition’s control), low, medium and high levels of nitrogen additions. Another six of them were used as species’ control group, the four installed cores around them had no nitrogen addition. The results showed that: 1) After 105 days in situ, for all the six species, summed dry weight, length and surface area measured in the four cores of the treatment group were significantly greater than the corresponding values in species’ control group. In aboveground biomass, however, only A. scoparia in the treatment group had significantly outweighed that in the species’ control group. 2) Irrespective of nitrogen additions levels, significant differences of length, diameter and surface area existed among the six species, which implied that species had their intrinsic species specific morphological traits. 3) In dry weight, length and surface area, the responses of all the six species to nitrogen addition levels were positive, significantly more roots were grew into the cores with higher nitrogen additions; while in specific root length, the responses were negative. 4) Perhaps the six species had a special nitrogen requirement, as interaction effects of species and addition levels in surface area were found significant. 5) The foraging precision of the six species to nutrient-rich patches had positive but insignificant correlation with root system size; there existed a significant positive correlation between the precision and the sensitivity to the designed patchy habiats. 6) Among the six species, A. scoparia, A. sacrorum and S. bungeana have higher sensitivity and precision than L. dahurica and A. melilotoides in terms of foraging the nitrogen addition cores or patches. It seems that fast growing species that dominate in early successional stage, like A. scoparia and S. bungeana in our case, obtained more benefits from nutrient patchy habitat. We advised that, in infertile lands, fertiliser be applied in a patchy way to accelerate the restoration of old fields as early as possible once they were abandoned.

14

Schemes Set for Protecting Parallel Generators with Different Capacity in the Integrated Power System

Ye Z., Wang G., Hu L, Fang M., Fu L., Fan X., Ma F.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 10a

162-165

EN

The output of power stations varies widely with the diverse operating modes in which the vessels integrated power system (IPS) works. Taking two parallel generators with different capacity for example, there are four possible protection schemes set for both the bus breaker and the main breakers of generators. The results show that the setting value used in each of four cases cannot offer appropriate protection for the normal operation of the system. For this reason, a solution is proposed, that is, the time-current principle in combination with the detection of voltage sag.

PL

Przy dwóch połączonych równolegle generatorach o różnej pojemności trzeba używać cztery układy zabezpieczające dla dwóch łączników szynowych i głównych łączników generatorów. W artykule zaproponowano nowe rozwiązanie układu zabezpieczającego bazujące na analizie czas-prąd i detekcji zapadów napięcia. (Układy zabezpieczenia generatorów równoległych o różnej pojemności dołączonych do zintegrowanego systemu energetycznego)

15

The relationships between aboveground biomass and Voronoi area of coexisting species in an old-field community

Du F., Xu X., Zhang X., Sui Y., Shao M., Hu L., Shan L.

Polish Journal of Ecology

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2012

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Vol. 60, nr 3

479-489

EN

Voronoi area of coexisting species in a community has an important role in determining their performances as it is related with the available resources around individuals. Biomass formed within certain Voronoi area probably can be a mark of species that characterised resource competition ability of coexisting species in natural community. In this article, we tried to probe the subject in the following three aspects: 1) what is the apparent relationship between individuals' aboveground biomass and their available Voronoi area for species in natural community? 2) what is the possible theoretic relationship between them? 3) additionally, whether there are any possible indices that can be elicited from species' occupied Voronoi area to reflect species' competitive ability. Using individual-based investigation of aboveground biomass and their corresponding positions, Voronoi area of all individuals of coexisting species in an old field community were computed. The growth of an individual could be regard as a process to compete for resources that is limited by the available area or volume encompassed by the neighborhood individuals. We extended logistic growth model to describe the relationship between Voronoi area and aboveground biomass of coexisting species by relating limiting rhizospheral resource with the Voronoi area around an individual. Theoretically, the individuals aboveground biomass is also controlled by factor-ceiling effects of Voronoi area. So the extended model was fitted with boundary analysis method. And also, their linear relationship was fitted. Under the prediction that competive ability is one of the main driving factors of community succession, two parameters as the Voronoi area of coexisting species and the Voronoi area per unit of aboveground biomass were used to check whether they can designate species' competitive abilities and competitive hierarchies. This was presented by fitting the two parameters with the successional niche positions that was represented by the ordination values along abandonment ages of old field communities in the local area. The results showed that: 1) For most species, the linear regression demonstrated that Voronoi area of an individual that occupied larger Voronoi area tended to have greater aboveground biomass. The nonlinear regression of showed that the relationship might depend upon species' growth characteristics, like shade tolerance and root proliferation. Generally, the relationship could be better fitted by the extended logistic growth model using boundary analysis method than by the linear regression, except for some shade-preferring or clone species. If factor-ceiling effects were considered, at the highest, about 48% of the variation of aboveground biomass could be interpreted by Voronoi area. For some other species with light preference or clone proliferation, the determination coefficient was around zero. 2) Species. averaged Voronoi area had significant and positive Kendall's tau-b and Spearman correlations with successional niches, and species' per-unit aboveground biomass positions of Voronoi area has significantly negative rank correlation with successional niche positions. These indicate that both of them can reflect species' competitive ability and hierarchy to some extent.

16

Responses of old-field vegetation to spatially homogenous or heterogenous fertilisation: implications for resources utilization and restoration

Du F., Xu X., Zhang X., Shao M., Hu L., Shan L.

Polish Journal of Ecology

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2012

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Vol. 60, nr 1

133-144

EN

A vailability and heterogeneity of resources have a strong influence on community biomass and diversity, which provided a valuable opportunity to evaluate the responses of vegetation on fertilization, to test whether fertilisation can accelerate vegetation restoration in infertile lands. In loess hilly region of China, most newly abandoned infertile lands often undergo heavy soil erosion. It is urgent to promote the restoration of these types of lands. As availability and heterogeneity of soil nutrients have a strong influence on plant community, we conducted a fertilisation experiment with three-factor treatments, to test whether fertilisation can promote the biomass and species richness of an Artemisia scoparia-dominated old field community. The three factors were: spatial patterns (homogeneity and heterogeneity), levels (low, medium and high), and scales (three levels with small, intermediate, and large patches) of fertiliser application. Above- and below-ground biomass and species richness were recorded. The responses of the plant community to the three factors were evaluated and compared with those of the control (no fertilisation). The results show that: (1) The application of fertiliser in either homogeneous or heterogeneous pattern significantly increased the above-ground and below-ground biomass of the plant community as compared with the control. (2) In heterogeneous conditions, the above-ground biomass in nutrient-rich patches was significantly greater than the expected value of 50%. Under intermediate and large scales of the low level and all scales of the medium and high levels, the proportion of 0.15 cm below-ground biomass was also significantly greater than 50%. (3) Both homogeneous and heterogeneous fertilisation greatly increased community richness as compared to the control. Fertilisation, particularly heterogeneous fertilisation, can effectively increase community biomass and diversity. Under patchy habitat, it seems that the responses of vegetation to heterogeneous fertilisation are related to the patches scale and the contrast among patches, nutrient usage efficiency, edge effects on plant and soil, and plant competition are responsible for the responses. The results also suggest that heterogeneous fertilisation should be applied widely in infertile old fields to accelerate secondary succession.

17

Preparation of crystal-controlled Y-TZP/Al2O3 nanocomposites

Fang Y., Zhang Y., Hu L.

Materials Science Poland

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2012

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Vol. 30, No. 4

348--354

EN

ZrO2-Y2O3-Al2O3 nanocrystalline powders with different grain sizes have been synthesized using a chemical coprecipitation method. Nano-powders were compacted uniaxially and densified in a vacuum hot-pressing furnace. Density, pore size distribution, grain size and composition of the composites were determined by various techniques, including BET gas absorption, field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). It has been shown that the porosity, grain and pore size of the ceramics can be controlled by the initial powder size and sintering temperature. Fully densified ceramics with narrow grain size distribution in the range of 100 500 nm could be obtained.

18

Study on the Initiation Capacities of Two Booster Pellets

Hu L., Hu S., Cao X.

Central European Journal of Energetic Materials

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2012

|

Vol. 9, nr 3

261-272

EN

The appearance of insensitive main charges has created new requirements in the booster pellets of the detonation train, specifically, the output of the booster pellet must be strong enough to initiate the insensitive main charge. Traditional cylindrical booster pellets have great difficulty in meeting the demands of the insensitive main charge for reliable detonation. A four-point-synchronous explosive circuit and an eight-point-synchronous explosive circuit were designed to initiate two booster pellets, designed on the basis of shock initiation theory and effective charge theory, as well as the shaped charge effect theory. The results show that booster pellet 1 and booster pellet 2, under multi-point-synchronous explosive circuits, can initiate standard main charge pellets with less explosive mass than an ordinary cylindrical booster pellet. The initiation capacity of booster pellet 2 is better than that of booster pellet 1.

19

Observations of the Effect of Cationic Surfactant DTANO3 on the Novel Belousov-Zhabotinskii Reaction Catalyzed by a Tetraazamacrocyclic Complex

Hu G., Zhang J. F., Chen L. L., Chen P. P., Wang W., Song J. M., Qiu L. G., Hu L.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 3

519-523

20

ZnO/MgO distributed Bragg reflectors

Huo B., Hu L., Zhang H., Zhao Z., Fu Q., Chen X.

Optica Applicata

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2009

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Vol. 39, nr 1

169--174

EN

ZnO/MgO distributed Bragg reflectors (DBRs) are grown by pulsed laser deposition. DBR samples grown at the same temperature and the same pressure show obvious reflections in transmission spectra. If there is a standing wave in the ZnO layers, it is evident that the full width at half maximum of the ZnO peak in photoluminescence spectra could be decreased when the sample reflects more photons whose wavelength is about 380 nm.