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Massive amounts of waste tires are produced globally, which brings great challenges to the disposal and recycling of used tires. Hydrothermal gasification is a promising option for recycling waste tires. The hydrothermal gasification of waste tires was evaluated based on the chemical equilibrium analysis along with the response surface methodology (RSM) in terms of subcritical temperature range (250–300 °C), transition temperature range (350–400 °C), supercritical temperature range (550–600 °C), supercritical pressure (22.5–30.5 MPa) and feedstock concentration (5–20 wt%). CH4 yield at 350 °C reached a maximum, 41.575 mmol/g. H2 yield increased from 0.0283 to 53.602 mmol/g with increasing the temperature from 250 °C to 600 °C. CH4 yield at the supercritical temperature increased with lifting the feedstock concentration, while H2 yield decreased. The optimal parameters regarding maximum H2 and CH4 yields in the subcritical temperature range were 300 °C, 22.5 MPa and 12.5 wt%, respectively, while they in the supercritical temperature range were 550 °C, 30.5 MPa and 5.4 wt%, respectively. RSM was more suitable for predicting H2 yield in the hydrothermal gasification of waste tires at subcritical and supercritical temperature ranges, but it was available for predicting CH4 yield in three temperature ranges. This study can provide basic data for the hydrothermal treatment of waste tires.

Ultrasound assistance was applied to friction stir transient liquid phase spot welding (FSTLPSW) to attain a high-quality dissimilar copper-aluminum joint in this study. Different ultrasound-assisted times were selected for comparing with the conventional condition without ultrasound. The interfacial microstructure evolution of conventional joint was analyzed combined with the measured temperature cycle. The ultrasound assistance improved the joint quality by regulating the interfacial microstructure. Cavitation erosion, broken IMC particles and thicker eutectic layer appeared in ultrasound-assisted joint. The highest tensile shear strength of 7.38 kN was obtained under the ultrasound-assisted time of 60 s which was 43.1 % higher than that of the conventional joint. The fracture location transferred from IMC layers to eutectic layer under the ultrasound assistance.

Decorating semi-conducting metal oxide with noble metal has been recognized as a viable approach to improve the sensitivity of gas sensor. However, conventional method which relys on noble metal nanoparticles is confronted with drawback of significantly increased cost. To maximize the atom efficiency and reduce the cost for practical industrial application, designing sensor material with noble metal isolated single atom sites (ISAS) doping is a desired option. Here, we report an atomically dispersed platinum on one-dimensional arranged porous γ-Fe2O3 nanoparticle composites as highly efficient ethanol gas sensor. The optimized sample (Pt1-Fe2O3-ox) exhibited a high response (Ra/Rg = 102.4) and good selectivity to ethanol gas. It is demonstrated only the Pt single atom sites with high valance can effectively promote the adsorption capacity to ethanol and consequently enhance the sensitivity of sensing process by changing the electrical structure of Fe2O3 support. This work indicates the single atom sites could play a vital role in improving the performance of conventional metal oxides gas sensors and pave way for the exploration of ISAS-enhanced gas sensor for other volatile organic compounds (VOCs).

A drying-autothermal gasification scheme with torrefied biomass as auxiliary feedstock was proposed for the first time in order to realize the decentralized treatment of sewage sludge in wastewater treatment plant. Thermodynamic equilibrium and energy flow balance for the proposed system were evaluated. A non-stoichiometric thermodynamic equilibrium model was applied to evaluate the effect of adding ratio of torrefied biomass on the autothermal gasification performance. A novel dual-check algorithm was developed to determine the molar numbers of syngas components and the injected air. The energy utilization ratio for the whole process was introduced to measure the ratio of the energy used in the whole system to the total input energy. High adding ratio of torrefied biomass was favor of lifting the cold gas efficiency, but it would lead to low energy utilization ratio in terms of sewage sludge treatment.

Single-atom catalysts not only maximize metal atom efficiency, they also display properties that are considerably different to their more conventional nanoparticle equivalents, making them a promising family of materials to investigate. Herein we developed a general host–guest strategy to fabricate various metal single-atom catalysts on nitrogen-doped carbon (M1/CN, M = Pt, Ir, Pd, Ru, Mo, Ga, Cu, Ni, Mn). The iridium variant Ir1/CN electrocatalyses the formic acid oxidation reaction with a mass activity of 12.9 $${{{\rm{A}}\,{\rm{mg}}^{-1}_{{\rm{Ir}}}}}$$ whereas an Ir/C nanoparticle catalyst is almost inert (~4.8 × 10−3 $${{{\rm{A}}\,{\rm{mg}}^{-1}_{{\rm{Ir}}}}}$$). The activity of Ir1/CN is also 16 and 19 times greater than those of Pd/C and Pt/C, respectively. Furthermore, Ir1/CN displays high tolerance to CO poisoning. First-principle density functional theory reveals that the properties of Ir1/CN stem from the spatial isolation of iridium sites and from the modified electronic structure of iridium with respect to a conventional nanoparticle catalyst. Single-atom catalysts maximize metal atom efficiency and exhibit properties that can be considerably different to their nanoparticle equivalent. Now a general host–guest strategy to make various single-atom catalysts on nitrogen-doped carbon has been developed; the iridium variant electrocatalyses the formic acid oxidation reaction with high mass activity and displays high tolerance to CO poisoning.

As a major air pollutant, SO2 has negative effect on the human health and environment. The desulfurization characteristics of two CaO samples (commercial one and the other one calcined from CaCO3) with high purity were examined by a thermo-gravimetric analyzer under circulating fluidized bed combustion-like condition. The influences of SO2 concentration (1000–4000 ppm), CO2 concentration (0–45%) and temperatures (800–950 °C) on the sulfation conversion degree of CaO samples were addressed, and sulfation kinetic parameters for the two samples were estimated based on the unreacted shrinking core model. The sulfation conversion degree of CaO calcined from CaCO3 at 900 °C and 2000 ppm SO2 was 68% higher than the commercial CaO. The sulfation conversion degree for the commercial CaO at 950 °C with 2000 ppm SO2 was one time higher than at 800 °C, and the sulfation conversion degree for the sample calcined from CaCO3 at 950 °C increased by about 31% compared to that at 800 °C. The calcium conversion degree of the sample calcined from CaCO3 was 0.59 in the absence of CO2, and the conversion degree with the CO2 concentration of 45% reduced by about 31%. The sulfation kinetics of two samples were appropriately described by the shrinking unreacted core model. The sample calcined from CaCO3 had a better sulfation activity than the commercial CaO.

The regulatory roles of mitogen-activated protein kinase (MAPK) signaling pathways on the hypothalamic−pituitary−gonadal axis (HPG axis) of Wenchang chicks under heat stress (HS) were investigated. Additionally, the crosstalk between these signaling pathways was explored. Immunohistochemical experiments and Western blotting were employed to quantify extracellular regulated protein kinases (ERK), c-Jun N-terminal kinases (JNK), and p38MAPK (P38). In female chicks, hypothalamic ERKs were upregulated in Weeks 1 and 2 in the HS group compared with the control group (CK), while JNK and p38 were downregulated (P < 0.05). Pituitary MAPKs were all downregulated in the HS group compared with the CK group in Week 3, but p38 was upregulated in Week 4 (P < 0.01). In the HS group, ovarian MAPKs were all upregulated compared with the CK group during Week 5, whereas ERK was downregulated in Week 6 (P < 0.01). In contrast to the patterns of MAPK expression in female chicks in the HS and CK groups, ERK in male chicks showed a completely opposite pattern in Weeks 1, 2, and 5, while p38 and JNK were downregulated in both female and male chicks under HS during Weeks 2 and 3. In the HS group, pituitary and testis MAPKs showed a pattern opposite to that observed in female chicks under HS in Week 5; MAPKs were all downregulated (P < 0.05). Thus, there are gender differences in the MAPK signaling pathways in the HPG axis in chicks, and these pathways showed plasticity. Early HS can enhance chick growth and development as well as promote developing in the MAPK signaling pathways in the HPG axis. However, after heated brooding was discontinued in chicks, long-term HS obstructed chick development and caused tissue and function injury to the HPG axis.

The artificial intelligence technique is utilized to improve evaluation of thermally induced solid-state reaction kinetics. A general regression neural network (GRNN) model was applied to directly determine the kinetic triplets, i.e., activation energy, pre-exponential factor, and mechanism model. The effect of number of heating rate on prediction performance of the GRNN model was assessed based on the estimation indictors. The obtained kinetic triplets based on the triple heating rates were considered to be accepted. The prediction ability of the GRNN model was very robust at more than three heating rates. The relative errors for kinetic parameters derived from five heating rates were within ± 4%, and the cognition rates for mechanism models were up to 99.6%. The developed GRNN model was successfully applied in the high-temperature synthesis of Li4Ti5O12/C composites. It is expected that the model also could be extended to estimate the kinetics of other solid-state reactions.

Grouting is an important method to reinforce fractured rock mass in underground engineering. To improve the grouting reinforcement effect of fractured rock mass, the theory of self-stress grouting reinforcement was put forward for the first time, and the self-stress grouting material was developed. The swelling stress of self-stress grouting material was tested by self-developed testing device to analyze the relationship between swelling stress and expansive agent content. Then, with cement, bentonite, silica fume, FZ expansive agent, accelerator, water reducer and water as raw materials, the effects of bentonite-cement ratio, silica fume content, accelerator content and water reducer content on the fluidity, initial setting time, uniaxial compressive strength at 3 days and 28 days of grouts were investigated by orthogonal test. Finally, the optimum proportion of the cement-based self-stress composite grouting material was applied to reinforce crushed coal blocks and the surrounding rocks of mine roadway, respectively. The results shown the optimum expansive agent content of the grout was 10%, corresponding swelling stress of 0.82 MPa. The proportion of the cement-based self-stress composite grouting material was bentonite-cement ratio of 1, FZ expansive agent content of 10%, silica fume content of 6%, accelerator content of 2.9%, and retarder content of 2.5%. The uniaxial compressive strength of the crushed coal blocks after reinforcement was 12.1 MPa, which was greater than the strength of the original coal. The cement-based self-stress composite grouting material had significant effect on the reinforcement of the surrounding rocks of mine roadway.

A series of concrete mixes with metakaolin (MK) content ranging from 0 to 30% and water/cementitious materials (W/CM) ratio varying from 0.30 to 0.50 were produced for performance testing. The results showed that adding MK up to 20% as ordinary Portland cement (OPC) replacement best improved the 28-day and 70-day cube strengths, whereas adding MK up to 30% as OPC replacement always increased the cohesiveness and decreased the sorptivity, but impaired the workability. Moreover, the cement equivalent factor (CEF), i.e. the equivalent mass of OPC per mass of MK added, for each performance attribute, including workability and cohesiveness, was evaluated. Whilst the actual CEF of MK was generally higher at a higher W/CM ratio and lower at a higher MK content, overall, the average CEFs were found to be 1.98, 2.17, 3.83, 1.93, 2.12, and 4.70 for slump, flow, cohesiveness, 28-day cube strength, 70-day cube strength, and sorptivity coefficient, respectively. These CEF values indicated that the MK is a highly effective cementitious material for improving the cohesiveness, strength, and durability. Moreover, it has been demonstrated that the CEFs for workability and cohesiveness are useful parameters in aiding the mix design of MK concrete., This research was funded by National Natural Science Foundation of China (grant number 51678161), Research Project of Guangdong Provincial Education Department of China (grant number 2018GXJK197), Guangdong Provincial Education Department Educational Reformation Project (grant number 595 in year 2018), Research Centre of Green Building Materials and Modular Integrated Construction Technology of Guangdong Province of China (grant number ZCZX201803), Featured and Innovative Project for Colleges and Universities of Guangdong Province (grant number 2017KTSCX061) and Pearl River S&T Nova Program of Guangzhou City (grant number 201906010064)

α-V2O5 (001) thin films were fabricated by reactive magnetron sputtering. The effects of the deposition temperature as well as the oxygen flux on the crystal structure, surface morphology and terahertz property were studied. The formation of vanadyl oxygen defect leads to a transient charge distribution that forms THz radiating dipoles in α-V2O5(001) surface. THz properties are closely related with the thermally reduced surface of α-V2O5 (001) films. Dynamics of the formation of surface oxygen vacancies accompanied with VO6 octahedral distortion is the key to understand the THz luminescence from the thermally reduced surface of V2O5.

A synergistic scheme of co-gasification of wet sewage sludge and torrefied biomass was proposed in order to get the hydrogen-rich syngas, which could avoid the dual energy input for drying of wet sewage sludge and steam generation. Co-gasification behavior of wet sewage sludge and torrefied biomass was evaluated by using a general non-stoichiometric thermodynamic equilibrium model developed based upon the Gibbs free energy minimization. The tenary plot of C H O system was used to evaluate the theoretical carbon formation performance at thermodynamic equilibrium state. The effects of mixing ratio and torrefaction severity on carbon conversion ratio, compositions of dry syngas, and H2 yield were also addressed. High mixing ratio of wet sewage sludge and high gasification temperature were required for the high carbon conversion ratio. The gasification temperature of 1100 K was a favorable level for the H2 yield and energy input. The optimal mixing ratio range of wet sewage sludge for low and middle temperatures torrefied biomass samples was between 30% and 40%, while that for high temperature ones was approximately 55%. This work could provide a feasible technical route and basic data for the resource and energy utilization of sewage sludge and biomass.

Chemical exergy of plastic waste is very critical for the optimization design of its thermochemical conversion system. The chemical exergy of six kinds of typical plastic wastes was calculated. The linear relationship between chemical exergy and high heating value for the samples was identified. The universal set of simulated multi-component plastic wastes was divided into five subsets based on the number of the components. The sample set was generated from five subsets by using the systematic sampling. Based on the sample set, the above linear relationship was validated for evaluating the chemical exergy of multi-component plastic wastes. The developed model had a good ability on predicting the chemical exergy of multi- component plastic wastes with a low error of less than 5%. This model required only the input of high heating value, which can be directly examined for the multi-component plastic wastes with unknown components. This study could provide a simple and effective tool for the evaluation of chemical exergy of multi-component plastic wastes.

Lignite is one of common applied fossil fuels worldwide, and solid wastes like biomass as well as sewage sludge are promising alternatives of fossil fuels. The isothermal combustion performances of lignite/solid wastes (eucalyptus bark and sewage sludge) briquettes between 500 °C and 800 °C in a bench-scale fixed bed furnace were examined based on a macro-thermogravimetric analysis approach. Compared with untreated samples, the average combustion rates of lignite and sewage sludge with the microwave treatment decreased, while those for treated eucalyptus bark increased. The drying, devolatilization and char combustion processes overlapped in the isothermal combustion for all samples. The treated lignite had a high aromatic hydrocarbon, while both the treated sewage sludge and eucalyptus bark had high hydroxyl and methyl group (CH3). After the microwave pretreatment, the fuel rank of lignite was prompted, while that for eucalyptus bark and sewage sludge degraded. Through the microwave pretreatment, the activation energies of lignite, sewage sludge, and eucalyptus bark grew from 15.45 to 21.20 kJ mol−1, 18.23–20.77 kJ mol−1, and 13.27–14.22 kJ mol−1. The study can provide some basic data for the energy utilization of lignite and solid wastes.

In situ synchrotron x-ray imaging and diffraction are used to investigate deformation of a rolled magnesium alloy under uniaxial compression at room and elevated temperatures along two different directions. The loading axis (LA) is either perpendicular or parallel to the normal direction, and these two cases are referred to as LA ⊥ 〈 c 〉 and LA ∥ 〈 c 〉 loading, respectively. Multiscale measurements including stress–strain curves (macroscale), strain fields (mesoscale), and diffraction patterns (microscale) are obtained simultaneously. Due to initial texture, { 10 1 ¯ 2 } extension twinning is predominant in the LA ⊥ 〈 c 〉 loading, while dislocation motion prevails in the LA ∥ 〈 c 〉 loading. With increasing temperature, fewer { 10 1 ¯ 2 } extension twins are activated in the LA ⊥ 〈 c 〉 samples, giving rise to reduced strain homogenization, while pyramidal 〈 c + a 〉 slip becomes readily activated, leading to more homogeneous deformation for the LA ∥ 〈 c 〉 loading. The difference in the strain hardening rates is attributed to that in strain field homogenization for these two loading directions.

We consider a class of non-linear integro-differential equations describing microfluidic measurements. We prove that under reasonable conditions, solutions to these equations are convex functions of a flow-rate parameter ξ used in metrology. The key elements of our analysis are: (i) elevation of ξ to an independent variable through reformulation of the problem as a partial-differential equation (PDE); and (ii) extension of techniques from the theory of ordinary differential equations to the PDE setting.

Clear recognition and rational construction of suitable active center for specific reaction is always of great significance in designing highly efficient catalysts. Herein, a dual-active-site copper catalyst (DAS-Cu) containing both CuN3 and CuN4 sites is reported. Such catalysts show extremely high catalytic performance (yield: up to 97%) toward oxyphosphorylation of alkenes, while catalysts with single active site (CuN3 or CuN4 ) are chemically inert in this reaction. Combined with theoretical and experimental results, the different roles of two different Cu active sites in this reaction are further identified. CuN3 site captures the oxygen and trigger further oxidizing process, while CuN4 site provides moderate adsorption sites for the protection of phosphonyl radicals. This work deeply discloses the significant cooperated role with two single-atomic sites in one catalytic active center and brings up a valuable clue for the rational design of better-performing heterogeneous catalyst.

We successfully prepared Fe and Co isolated single atoms on metal-organic framework derived nitrogen-doped carbon (FeCo-ISAs/CN) by an adsorption-calcination strategy. The obtained FeCo-ISAs/CN exhibited top-level catalytic reactivity for the alkaline oxygen reduction reaction (ORR) with a half-wave potential of 0.920 V, which was 70 mV more positive than that of commercial Pt/C. Moreover, the catalyst was durable and showed negligible activity decay in the alkaline ORR during 5000 voltage cycles.

Heteroatom-doped Fe-NC catalyst has emerged as one of the most promising candidates to replace noble metal-based catalysts for highly efficient oxygen reduction reaction (ORR). However, delicate controls over their structure parameters to optimize the catalytic efficiency and molecular-level understandings of the catalytic mechanism are still challenging. Herein, a novel pyrrole-thiophene copolymer pyrolysis strategy to synthesize Fe-isolated single atoms on sulfur and nitrogen-codoped carbon (Fe-ISA/SNC) with controllable S, N doping is rationally designed. The catalytic efficiency of Fe-ISA/SNC shows a volcano-type curve with the increase of sulfur doping. The optimized Fe-ISA/SNC exhibits a half-wave potential of 0.896 V (vs reversible hydrogen electrode (RHE)), which is more positive than those of Fe-isolated single atoms on nitrogen codoped carbon (Fe-ISA/NC, 0.839 V), commercial Pt/C (0.841 V), and most reported nonprecious metal catalysts. Fe-ISA/SNC is methanol tolerable and shows negligible activity decay in alkaline condition during 15 000 voltage cycles. X-ray absorption fine structure analysis and density functional theory calculations reveal that the incorporated sulfur engineers the charges on N atoms surrounding the Fe reactive center. The enriched charge facilitates the rate-limiting reductive release of OH* and therefore improved the overall ORR efficiency.

This paper analyzes the present highway situation of remote areas in Inner Mongolia that traditional charge cannot meet the demand. According to the advanced communication technologies of highway and the data transmission requirement for highway communication system, we introduced a method of data transfer based on .NET Framework. The results show that adopting VB.NET and SQL Server 2005, the data of wireless transmission between toll station and sub-center security has been obtained, and the stability of the system has been analyzed.

The rabbitfish Siganus fuscescens is an economically valuable species that is widely distributed throughout the estuaries, intertidal, and offshore coasts of the Indo-Pacific and eastern Mediterranean. Ten novel microsatellite loci from the genome of S. fuscescens were developed using the fast isolation protocol with amplified fragment length polymorphism of sequences containing repeats. Polymorphisms in these 10 microsatellite markers were determined from 32 wild individuals. The number of alleles per locus and the polymorphism information content ranged from 2 to 5 and from 0.059 to 0.668, respectively. The observed and expected heterozygosities varied from 0.063 to 0.781 and from 0.062 to 0.731, respectively. Although 1 locus (LZY-X7, P < 0.005) showed significant deviation from the Hardy-Weinberg equilibrium, no deviations were detected in the other 9 loci. These microsatellite loci may be useful for further population genetic studies, conservation studies, population structure assessment, and linkage map construction of S. fuscescens.

The pen shell, Atrina vexillum Born, is an edible shellfish that is widely consumed in the Asia-Pacific region. In this study, 11 polymorphic microsatellite loci were isolated from A. vexillum, and 30 wild individuals were used to evaluate the degree of polymorphism of these markers. The number of alleles per locus ranged from 3 to 8. The polymorphism information content varied from 0.199 to 0.831. The observed and expected heterozygosities were 0.1000-0.8667 and 0.1244-0.8356, respectively. Two loci deviated significantly from the Hardy-Weinberg equilibrium (HWE) after a Bonferroni correction, while the other nine loci were at HWE. These microsatellite loci will be useful in further studies on population genetic analyses, and will provide important genetic data for the conservation and recovery of A. vexillum.

Lunella coronata granulata, from the family Turbini-dae, is an economically important species. The first set of 10 poly-morphic microsatellite loci was screened from L. coronata granulata, and 30 individuals were used to analyze the degree of polymorphism in these loci. The level of observed and expected heterozygosity was 0.0667-0.7333 and 0.0644-0.6628, respectively. The polymorphism information content varied from 0.305 to 0.559. Eight loci were in Hardy-Weinberg equilibrium (HWE) (P > 0.05), while two loci devi-ated significantly from the HWE after Bonferroni's correction (P < 0.005). The isolated microsatellite loci can be utilized in studies of population genetic analysis and they provide important genetic mark-ers for construction of genetic linkage maps and genetic breeding of L. coronata granulata resources.

Fenneropenaeus penicillatus, with high protein and low fat, is a commercially important aquatic product in China. Microsatellite loci were developed according to the protocol of fast isolation by amplified fragment length polymorphism of sequences containing repeats. Eight new polymorphic microsatellite markers for F. penicillatus were identified, and 32 wild individuals were used to evaluate the degree of polymorphism of these markers. The polymorphism information content ranged from 0.2703 to 0.7598, and the number of alleles per locus varied from 3 to 6. The observed and expected heterozygosities were 0.1613-0.5556 and 0.2347-0.7387, respectively. No significant deviations from Hardy-Weinberg equilibrium (P > 0.00625) were detected. These polymorphic microsatellite loci will be useful to study the genetic diversity and population structure of F. penicillatus.

High temperature wear properties of titanium carbide (TiC) composite coatings fabricated by laser cladding with titanium powder and varied percentages of carbon nano-tube (CNT) powders on titanium substrates have been tested by pin-on-disk wear under dry sliding conditions. The results reveal that TiC composite coatings fabricated with proper addition of CNT give promising high temperature wear resistance which is ten times higher than that of the titanium substrate. The high temperature wear behavior and friction coefficient of the titanium substrate and the composite coatings were investigated. It was found that the wear behavior of the dominant wear mechanism of the TiC composite coatings is adhesive wear and oxidation, whereas the Ti substrate exhibits abrasive wear, adhesive wear, serious plastic deformation, and oxidation at high temperature. The improvement of the wear resistance is believed to be attributed to the reinforcement phase of TiC which can also provide high hardness according to the microstructure observation of the composite coatings by SEM, EDX and microhardness measurements.

This study aimed to screen single nucleotide polymorphisms (SNPs) in the chicken gap junction protein alpha 1 (GJA1) gene, and to investigate their association with five growth traits measured in 269 chickens encompassing Chinese indigenous Beijing-You (BJY) and commercial Cobb broiler (CB) populations. Four variants were detected in the chicken GJA1 gene, in which one synonymous mutation was located in an exon (C61223231T or c.-1110 C>T), two in an intron (A61229799C or c.5460 A>C, T61229928A or c.5589 T>A) and one in the promoter (A61230599C or c. 6260 A>C) regions. Genotyping was performed by high-resolution melting analysis (SNP in an exon) and DNA sequencing (SNP in the introns and promoter). Association analysis revealed that each SNP had a significant effect on growth traits in chicken. A higher level of genetic diversity was observed in the indigenous BJY breed than in the commercial CB breed. Strong linkage disequilibrium was observed between the C61223231T and A61229799C polymorphisms, and four previously undiscovered haplotypes (CA, TC, CC, TA) were constructed from those two mutations. Association analysis between haplotype combinations (diplotypes) and growth traits was highly significant where diplotype CC + CC was dominant for all traits. We speculated that GJA1 either is a major gene, or is associated with a major gene, affecting chicken growth traits. Therefore, further studies are needed in large populations to evaluate polymorphisms located in different regions of this gene, as well as its functional study, to better understand its role in muscle development in chicken.

In this paper we explore the major, minor and some trace elements of sixty-five glass beads from eighteen oasis sites both north and south of the Taklamakan Desert, the ancient centre of the Silk Routes linking East and West; the samples date from the Warring States period (475–2211 BCE) to the Tang Dynasty (618–907 CE). Using a high-resolution portable XRF spectrometer, with special attention to issues of surface weathering and sample preparation, we obtained quantitative chemical compositional data that, when combined with archaeological context and the technology of bead manufacture, provide the basis for an understanding of both changes in glass type over time, and possible source areas for the Xinjiang glasses. While glass beads at the early sites (1st c. BCE to 4th c. CE) were coming primarily from Kushan-controlled territories in northern India, Pakistan and Afghanistan, with a small contribution from central China, most of the later glass (4th–10th c. CE) is similar to that produced in the Sasanian Empire at such sites as Veh Ardashir in central Iraq. These changes most likely reflect changing cultural and economic conditions in the Silk Road towns.

The as yet unresolved microstructure of the periodic layers formed in the reactive diffusion system Mg/SiO(2) was clarified by using high-resolution field-emission SEM. The periodic layered structure actually consists of the single-phase layer of Mg(2)Si and the two-phase layer of (Mg(2)Si + MgO) alternated within the reaction zone. According to the experimental observations and in line with the diffusion-induced stresses model, the mechanism controlling this phenomenon could be attributed to the stresses induced by the difference in interface growth rates of Mg(2)Si and MgO phases within the layer. When the elastic deformation of the slow-growing aggregated-MgO phase reaches its elastic maximum, it will be split off from the reaction front by the neighboring Mg(2)Si phase and a new periodic layer forms. The computer simulation results are coinciding well with the experimental data. (C) 2009 Elsevier Ltd. All rights reserved.

The influences of ultrasonic field to polishing performance of Polishing Based on Coupling Vibration of Liquid (PCVL) are analyzed here. The simulation results shows that sound field in the original polishing device is rather uneven due to the existence of standing wave. To obtain better polishing performance, the experimental equipment was modified. Uniformity of the sound field was improved by preventing standing wave, thus a better surface quality could be achieved. Furthermore, a higher machining efficiency could be also obtained because sound intensity was strengthened at the same time. From the results serials of experiments, the improvements made by modified equipment are clearly shown.

Megalonibea fusca is a commercially important large edible fish. In this study, the first set of 10 polymorphic microsatellite loci for M. fusca was developed and characterized. The number of alleles per locus ranged from two to five, with the observed and expected heterozygosities ranging from 0.0667 to 0.7667, and from 0.0644 to 0.5828, respectively. Most of the loci were in Hardy-Weinberg equilibrium (P > 0.05), except for two loci (Mf25 and Mf30) after a Bonferroni's correction (P < 0.005). These informative microsatellite markers will be useful in further studies of the population and conservation genetics of this species.

Icing problems on road in Da Hinggangling forest region, northwest of China, are very serious. Many measures (blind ditch, pit for containing ice, fences/dams for blocking ice, insulated drain, etc.) have been used in this cold regions but they were not always effective. This paper analyses the formation reasons of icing and the disabled reasons of the old measures and represented a set of composite measures applied to control the icing problem on road in Da Hinggangling forest region. Results show that the frosty climate and the complex hydrology conditions and the inadequate field exploration are the main reasons that led the prevention measures to be disabled. The innovation of the technique is the “double-drainage openings” insulated drainage system. Practice proved that it had good effect on control icing problem on road, and also it could protect woods resource and ecology environment.

The marbled rockfish, Sebastiscus marmoratus, is an important commercially near-shore fish inhabiting littoral rocky bottoms from Japan to the East China Sea. Eleven polymorphic microsatellite loci were isolated from S. marmoratus and the polymorphism of these loci was observed in 32 samples from one wild population. The number of alleles ranged from 2 to 8. The polymorphism information content ranged from 0.155 to 0.752. The levels of the observed and expected heterozygosity were 0.186–0.969 and 0.170–0.782, respectively. Only one locus (Sm3-63) deviated from Hardy–Weinberg equilibrium. These microsatellite markers can provide a useful tool for further study on genetic diversity and conservation of S. marmoratus.

A single crystal silicon rotary microactuator for hard disk drives (HDD) is described in this paper. The microactuator is mounted between the slider and suspension and drives the slider on which a magnetic head element is attached. The microactuator has electrically isolated microstructures with an aspect ratio 20:1 directly processed from a single crystal silicon substrate. It consists of a stator attached to the silicon substrate by bus bar, and a movable rotor connected to an anchored central column via spring beams. Both the stator and the rotor are suspended from the silicon substrate. When a voltage is applied to the actuator, the microactuator will drive the head to move in tracking direction by the rotational motion of the rotor. The microactuator prototype with overall dimensions 1.4 mm ×1.4 mm ×0.18 mm has been successfully fabricated. The results of finite element method (FEM) simulation demonstrate that the microactuator has a better dynamic performance in a Head Gimbal Assembly (HGA) for hard disk drives. Experiments show that ±0.6 μm equivalent displacement of the head element in tracking direction is achieved under the driving voltage 20 V. The frequency response testing results of the microactuator bonded with a slider indicate that the microactuator is feasible to operate as a fine actuator in HDD.

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Ten polymorphic microsatellite loci in Fenneropenaeus penicillatus were isolated and characterized. Microsatellite polymorphism was tested by using 30 individuals from one wild population. The results showed that the number of alleles per locus and the polymorphism Information Content ranging from 3 to 7 and from 0.1813 to 0.6087, respectively. The observed and expected heterozygosity were 0.1379–0.2727 and 0.1308–0.5597, respectively. The loci identified in this study could provide a useful tool for ongoing population genetic structure analysis of F. penicillatus.

Acrossocheilus labiatus Regan occurs in the clear mountain streams in the east of Asia. Eighteen microsatellite loci were isolated from A. labiatus and fifteen loci were polymorphic observed in 30 samples tested. The number of alleles per locus ranged from 2 to 10. The polymorphism information content varied from 0.090 to 0.825. The observed and expected heterozygosities ranged from 0.069 to 0.900 and from 0.067 to 0.844, respectively. Although significant deviations from Hardy–Weinberg equilibrium were detected for three loci (HC-G11-1, HC-C3-3 and HC-G8-1, P 0.05). These microsatellite loci will be useful for the further study of population genetic analysis and subsequently provide important genetic data for the conservation and recovery of the A. labiatus resources.

In this study, the thermomechanical behavior of shape memory alloy (SMA) that is connected in series with a viscoelastic solid is studied. The viscoelastic materials are simplified to two-element spring–dashpot models: Maxwell model and Kelvin model. The constitutive equation of SMA depicted by Brinson's model is coupled with the governing equation of viscoelastic solid to predict the stress history in SMA. It is found that the viscosity coefficient η and modulus E in viscoelastic solids have significant effects on the stress response of SMA.

Siganus fuscescens, which is a small commercially important marine fish, is wildly distributed in shallow waters throughout the tropical and subtropical Indo-Pacific and Eastern Mediterranean regions. It is part of a group known as rabbitfish. Fifteen new polymorphic microsatellite markers for S. fuscescens were identified, and 32 wild individuals were used to evaluate the degree of polymorphism of these markers. The number of alleles per locus ranged from 2 to 12, and the polymorphism information content ranged from 0.210 to 0.849. The observed and expected heterozygosities were 0.142-0.808 and 0.225-0.853, respectively. Although significant deviations from Hardy-Weinberg equilibrium were detected at 2 loci (Sf1-37-2 and Sf1-47), no significant deviations were detected at the other 13 loci. These microsatellite markers will provide a useful tool for studies on genetic diversity and differentiation of S. fuscescens.

Eight novel microsatellite loci from the genome of Fenneropenaeus penicillatus Alcock were developed using the protocol of fast isolation by amplified fragment length polymorphism of sequences containing repeats (FIASCO). Thirty (30) wild individuals were used to analyze the polymorphism of these eight microsatellite markers. The results show that the number of alleles per locus and the polymorphism information content ranged from 2 to 7 and from 0.2076 to 0.7484, respectively. The observed and expected heterozygosity were 0.1724 to 0.9130 and 0.1639 to 0.7314, respectively. These microsatellite primers will be used for further population genetic studies, constructing genetic linkage maps or locating quantitative trait locus (QTL) of F. penicillatus Alcock. Keywords: Genetic markers, Fenneropenaeus penicillatus Alcock, microsatellites

The switching control strategy needs to design the switching surface and the control signal. In this paper, the control effect and the control process are studied for different control strategy based on dynamics method. For autonomous van der pol system, the orbit can be suppressed to an equilibrium when the switching-surface is chose to include equilibrium; otherwise the orbit only can be controlled to a sliding limit cycle of small amplitude. Crossing-sliding bifurcation and switching-sliding bifurcation is common route from crossing orbit to full-sliding orbit, and grazing-sliding bifurcation is common route from crossing orbit to equilibrium. The control strategy is robust to the disturbance of parameter and control signal once the steady full-sliding orbit is achieved.