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As a major group of insects, locusts frequently cause agricultural damage, however, they have high economic value due to their rich nutritional content. In this paper, we systematically summarise the research results on the species, distribution, and functional composition of locusts in China over the past three decades and analyse the differences in research results in relation to experimental methods, locust species, and the experimental dates. In addition, we also introduce the methods for obtaining mass locusts, and discuss the edible, medicinal and feed usage of locusts, and prospect the exploitation of locust resources in order to provide a reference for locust-related research.

Optimisation of lubricant supply to bearings has considerable benefits in terms of energy saving and smooth running. This paper presents a study on the hydrodynamic lubrication of sliding contact with various supplied lubricant quantities. Experiments were conducted with an optical slider-bearing test rig. Under limited lubricant supply (LLS), there exists a critical speed beyond which film thickness no longer increases with increasing speed due to starvation at the inlet. The critical speed significantly depends on lubricant quantity, as well as lubricant viscosity and load. Comparison between experimental and theoretical results indicates that the starved films have certain load-carrying capacity and viscous resistance. Under LLS, film thickness is a sensitive function of supply lubricant volume, but friction is not.

The phase composition, microstructural evolution and magnetocaloric properties of LaFe11.8S1.2 strip-casting flakes annealed at different temperatures and annealing times were investigated. The phase constitution and microstructure of strip-casting flakes are sensitive to annealing temperature, 1373K was found to be the optimum temperature for 1:13 phase formation. The microstructure and magnetocaloric properties changed with annealing time due to the diffusion of Fe and Si atoms. Samples annealed at 1373K for 10h reveal a high content (89.40 wt%) of the 1:13 phase and exhibited a maximum entropy change (−ΔSM)max of 16.89J/(kg·K) at 187K. These annealed LaFe11.8S1.2 strip-casting flakes are ideal master alloys for powder metallurgy fabrication of the heat exchangers used inactive magnetic regenerator prototypes.

Microstructure evolution during the homogenization heat treatment of an Al-Mg-Si-Fe-Mn (AA6xxx) alloy was investigated using a combination of modelling and experimental studies. The model is based on the CALPHAD-coupled homogenization heat treatment model originally developed for AA3xxx alloys (i.e., Al-Mn-Fe-Si). In this work, the model was adapted to the more complex AA6xxx system (Al-Mg-Si-Mn-Fe) to predict the evolution of critical microstructural features such as the spatial distribution of solute, the type and fraction of constituent particles and dispersoid number density and size distribution. Experiments were also conducted using three direct chill (DC) cast AA6xxx alloys with different Mn levels subjected to various homogenization treatments. The resulting microstructures were characterized using a range of techniques including scanning electron microscopy, electron microprobe analysis (EPMA), XRD, and electrical resistivity measurements. The model predictions were compared with the experimental measurements, and reasonable agreement was found.

The effect of Pr40Co60 addition on the structure, thermal conductivity, magnetic, magnetocaloric and mechanical properties of sintered LaFe11.6Si1.4/Pr40Co60 bulk composites were investigated. The addition of Pr–Co alloy has important effects on these properties due to the diffusion of Pr and Co into the La(Fe,Si)13 phase during sintering. After 6 h of sintering at 1373 K, these composites exhibited a gradual increase in Curie temperature (TC) from 220 K to near room temperature with relatively large maximum magnetic entropy change (–∆SM)max of 2.7–2.9 Jkg–1 K–1 under 0–2 T external magnetic field change. The diffusion of Pr and Co atoms into 1:13 majority phase facilitates 1:13 phase formation, while the Co content of the Pr-Co binder could be used to tune the TC but resulting in the reduced (–∆SM)max in the composites. The composites exhibit high compressive strength (σbc)max of up to 550 MPa and thermal conductivity (λ) of up to 10.64 Wm–1 K–1. Thus, these materials are promising candidates for near room temperature refrigeration.

LaFe11.6Si1.4/Ce2Co7 composites were prepared using strip casting flakes (SC-flakes) and heat treated flakes (HT-flakes) by hot pressing, denoted as SC-HP and HT-HP, respectively. Subsequently, additional heat treatment was performed. The microstructure evolution, phase constitution, magnetocaloric and mechanical properties of these SC-HP and HT-HP samples over a large range of heat treatment temperatures and times were compared. Heat treatment at 1373 K for 12 h resulted in Ce and Co diffusion into La(Fe,Si)13 particles. An increase of Tpeak from 228 to 289 K and a large (–ΔSM)max increase from 1.89 to 5.01 J kg−1 K−1 (ΔH = 2 T) was observed in SC-HP samples. Combining hot pressing and heat treatment considerably reduces processing time. 90% of theoretical density, compressive strength greater than 450 MPa, large (–ΔSM)max of ~4.73–5.01 J kg−1 K−1 and good thermal conductivity (λ) above 5.5 Wm−1K−1 were also achieved, suggesting the practical use of such heat treated composites with attractive magnetocaloric, mechanical and thermal properties.

Excessive thermal stresses caused by temperature fluctuations can result in thermal fatigue in the piping system of a nuclear power plants (NPPs). The phenomenon of thermal stratification and turbulent penetration in a pipe can lead to temperature fluctuations, and have attracted much attention of the researchers who deal with NPPs. In particular, this phenomenon in the pressurizer surge line has been assessed as one of the significant safety and technical issues due to its high rate of occurrence. This work focuses on a fundamental description of the thermal stratification and turbulent penetration in a pressurizer surge line using experiment and computational fluid dynamics (CFD) simulation based on the FLUENT 6.3.26 code. In this study, CFD simulation with the LES turbulence model is proved to be an accurate and effective method of studying thermal stratification in a pressurizer surge line. Details of turbulent penetration have also been studied in this paper. A criterion of determining the depth of turbulent penetration has been proposed, and the main frequency of the velocity fluctuations of turbulent penetration in a surge line is found to be a continuous frequency band, and not a fixed value.

The demand for Al–Mg–Si extrusion alloys in the transportation sector is increasing rapidly. An important aspect of the process is high temperature extrusion and in particular, the breakthrough force for the extrusion press. The breakthrough force varies as a function of the extrusion ratio, extrusion speed and temperature, the complexity of the profile and the flow stress of the alloy. Further, Mn and Cr are often added to the alloy which form dispersoids during homogenization which precipitation strengthen the alloy at high temperature. This work presents a new approach to calculate the volume fraction of dispersoids using electron microprobe analysis, electrical resistivity measurements and transmission electron microscopy (TEM). The new method substantially increases the accuracy of the volume fraction determination compared with traditional image analysis or TEM since the volume of material sampled is much larger avoiding effects of local segregation. Using the volume fraction and dispersoid size measurements, a high temperature flow stress model based on dislocation theory has been developed. It is shown to describe the high temperature flow stress measurements to within 5% in 95% of the cases. The model was validated by independent experimentation where it predicted the flow stress within 5% accuracy. The flow stress model can be used independently based on experimental quantification of the dispersoids or as part of a through process model which includes a KWN based precipitation model for dispersoids and then implemented as constitutive equation for a FEM based model of the extrusion process.

A resilient robot can recover its original function after a partial damage. In this paper, a novel under-actuated resilient robot named ReBot is presented. ReBot is an under-actuated robotic system and it consists of one type of module, which realizes the under-actuated characteristic with the whole robot. In ReBot, the module is designed as a cube structure with two rotational DOFs. The module is designed such that one can connect to another with the function of self-locking and switching between an active and a passive connection. The evolution of the configuration of an entire robotic system is performed autonomously. A preliminary experiment is carried out to show that the design requirement can be achieved.

The thermal stress caused by thermal stratification in the pipelines of nuclear plants can easily induce thermal fatigue. Predicting the temperature fluctuations at the inner wall in the pipeline without destroying the integral structure of the pipeline is one way of preventing accidents and ensuring safe operation in nuclear plants. In this work, the conjugate gradient method (CGM) is applied to solve the two-dimensional inverse heat conduction problem (IHCP) with multi-variables, in order to estimate the unknown temperature fluctuations at the inner wall of a cross profile, the temperature fluctuations of the fluid near the inner wall, and the heat convection coefficient between fluid and the inner wall of the cross profile in the pressurizer surge line, based on experimental outer wall temperature measurements. The accuracy of the inverse algorithm is then examined by comparing the estimated outer wall temperatures with the experimental temperatures. The numerical results show that the inner wall temperature of the cross profile can be accurately estimated by using the inverse algorithm for the test case considered.

To improve the slab quality, it is essential to design an innovative model for understanding the bubbles’ behavior in the continuous casting mold. However, the influence of interaction of bubbles on the motion of dispersed phases has not been considered in most of mathematical simulation models. The purpose of the current work was to establish a new model to simulate the motion of gas bubbles in the mold. In this paper, the mathematical model being related to the interaction of bubbles (coalescence, bounce and breakup) was established using the user-defined functions to predict the behavior and distribution of gas bubbles. Introducing the interaction of bubbles, the size of bubbles will change in the process of collision and broken, so the results can give a good explanation to the motion of different size bubbles, and the phenomena of bubbles coalescence, bounce and breakup actually exist. The results show that the larger bubbles float up to the top surface as soon as they get out of the ports, while the smaller bubbles following the flow arrive at the narrow surface. The proposed mathematical model can described the behavior of bubbles exactly in the steel continuous casting process.

Knowledge of the elastic wave velocities of hydrate-bearing sediments is important for geophysical exploration and resource evaluation. Methane gas migration processes play an important role in geological hydrate accumulation systems, whether on the seafloor or in terrestrial permafrost regions, and their impact on elastic wave velocities in sediments needs further study. Hence, a high-pressure laboratory apparatus was developed to simulate natural continuous vertical migration of methane gas through sediments. Hydrate saturation (S h) and ultrasonic P- and S-wave velocities (V p and V s) were measured synchronously by time domain reflectometry (TDR) and by ultrasonic transmission methods respectively during gas hydrate formation in sediments. The results were compared to previously published laboratory data obtained in a static closed system. This indicated that the velocities of hydrate-bearing sediments in vertical gas migration systems are slightly lower than those in closed systems during hydrate formation. While velocities increase at a constant rate with hydrate saturation in the closed system, P-wave velocities show a fast–slow–fast variation with increasing hydrate saturation in the vertical gas migration system. The observed velocities are well described by an effective-medium velocity model, from which changing hydrate morphology was inferred to cause the fast–slow–fast velocity response in the gas migration system. Hydrate forms firstly at the grain contacts as cement, then grows within the pore space (floating), then finally grows into contact with the pore walls again. We conclude that hydrate morphology is the key factor that influences the elastic wave velocity response of methane gas hydrate formation in vertical gas migration systems.

Using less lubricant is currently a trend in tribology design to address fuel economy and environment concerns. The present study was conducted to identify how an oleophilic lubrication track bounded by oleophobic areas achieves efficient lubrication under limited lubricant supply (LLS) conditions. Findings showed that the stepped wettability formed at the border of the oleophilic track can reduce the coefficient of friction and wear for steel ball-on-steel plate contact in a mixed lubrication regime, and the width of the oleophilic track plays an important role. Correspondingly, optical interferometry measurement showed that the stepped wettability can improve lubricant replenishment and increase the film thickness. The unbalanced interface from the stepped wettability enhances the replenishment of the lubricant on the contact track.

We study D 0 D ¯ 0 pairs produced in e + e − collisions at s = 3.773 GeV using a data sample of 2.92 fb−1 collected with the BESIII detector. We measured the asymmetry A K π CP of the branching fractions of D → K − π + in CP-odd and CP-even eigenstates to be ( 12.7 ± 1.3 ± 0.7 ) × 10 − 2 . A K π CP can be used to extract the strong phase difference δ K π between the doubly Cabibbo-suppressed process D ¯ 0 → K − π + and the Cabibbo-favored process D 0 → K − π + . Using world-average values of external parameters, we obtain cos δ K π = 1.02 ± 0.11 ± 0.06 ± 0.01 . Here, the first and second uncertainties are statistical and systematic, respectively, while the third uncertainty arises from the external parameters. This is the most precise measurement of δ K π to date.

Focal brain ischemia, if its duration is long enough, will lead to irreversible brain tissue pan-necrosis or infarction in the ischemic territory. However, if adequate blood supply to ischemic tissue is restored within a short period of either focal or global brain ischemia, neuronal death may occur selectively in some populations of neurons, whereas the others as well as glial and vascular cells are preserved, which is commonly referred to as selective neuronal death. It is generally held that acute ischemic cell death in the ischemic core after permanent or a long period of ischemia is typical necrotic cell death, as manifested by a cascade of events of energy failure, breakdown of transmembrane ionic gradients, cell swollen, followed by the loss of cell membrane integrity to initiate an inflammatory response. However, whether selective neuronal death is necrotic, apoptotic, or autophagic, cell death has been a subject of debate. This chapter will discuss the current status of neuronal death mechanisms after brain ischemia.

As a β2 integrin family member, Mac-1 plays an important role in the inflammatory response. Inflammation and lung injury are closely associated, but the involvement of Mac-1 in the occurrence and development of such pathologies remains poorly understood. We aimed to investigate the relationship between Mac-1 deficiency and respiratory failure in Mac-1 knockout {Mac-1-/-} mice, using C57BL/6J mice as a control. The newborn survival rate of Mac-1-/- mice was calculated, and mouse lung tissue was treated with hematoxylin and eosin and subjected to immunofluorescent staining. Moreover, western blotting and immunohistochemistry were used to detect the expression of molecules specific to type I and type II alveolar epithelial cells, as well as alveolar surfactant proteins secreted by the latter. Survival of Mac-1-/- pups was significantly lower than that of newborn C57BL/6J mice. In a float test, lung tissues from C57BL/6J mice were buoyant, whereas those of Mac-1-/- mice were not. Compared with C57BL/6J mice, expression of proSP-C {specific to type II alveolar epithelial cells} and alveolar surfactant proteins in Mac-1-/- mice was not significantly different, implying that type II cell function was unaltered. However, western blotting revealed expression of T1α, Aqp5, and Snx5 {type I alveolar epithelial cell markers} in Mac-1-/- mice to be significantly decreased {P < 0.05}. In conclusion, Mac-1 may play an important role in respiratory failure. Its absence leads to this condition not by influencing type II alveolar epithelial cells or their secreted surfactant proteins, but rather by reducing type I alveolar cell numbers.

Autonomous Aerial Vehicle equipped with RF sensor provides a promising solution for a wide range of applications including search and rescue, vehicle localization, and navigation. We investigate such a micro UAV system and localization and navigation algorithms based on RF sensing. Our algorithm uses a particle filtering process to continuously monitor the RF signal from the target and estimate its most likely location. To improve the accuracy of the location estimation, our method uses a novel validation algorithm to screen the raw RF measurements and a scale estimation algorithm to model extrinsic parameters such as antenna gain. Experiment results indicate that the proposed system is able to navigate the micro UAV to the target device effectively within its RF range. An average location error of 3 meters is observed.

We investigate a vision-based vehicle tracking method which allows an unmanned aeriel vehicle(UAV) to track and follow a ground vehicle in coordinated Air-Ground operations. The UAV detects a customized Apriltag attached on the ground vehicle and estimates its motion status. We use a novel embedded-tag design to allow the UAV detect and lock the ground vehicle in both high and low altitude. The dynamic range achieved is from 0.3 meters to 10 meters. The motion-status estimation is improved using an optimum tag selection (as observation source) algorithm and a modified particle filter algorithm. The proposed algorithm improves the motion estimate accuracy significantly by 20%.

We study the decays of the J / ψ and ψ ′ mesons to π + π − π 0 using data samples at both resonances collected with the BES III detector in 2009. We measure the corresponding branching fractions with unprecedented precision and provide mass spectra and Dalitz plots. The branching fraction for J / ψ → π + π − π 0 is determined to be ( 2.137 ± 0.004 ( stat. ) − 0.056 + 0.058 ( syst. ) − 0.026 + 0.027 ( norm. ) ) × 10 − 2 , and the branching fraction for ψ ′ → π + π − π 0 is measured as ( 2.14 ± 0.03 ( stat. ) − 0.07 + 0.08 ( syst. ) − 0.08 + 0.09 ( norm. ) ) × 10 − 4 . The J / ψ decay is found to be dominated by an intermediate ρ ( 770 ) state, whereas the ψ ′ decay is dominated by di-pion masses around 2.2 GeV/ c 2 , leading to strikingly different Dalitz distributions.

Growth hormone-releasing hormone (GHRH) and pituitary adenylate cyclase activating polypeptide (PACAP) regulate development and somatic growth in teleosts; they may be associated with sexual growth dimorphism in the half-smooth tongue sole (Cynoglossus semilaevis). We found that the full-length GHRH and PACAP gene sequences obtained from females and males consist of 4160, 4159, 2425, and 2446 bp, respectively, each of which includes four exons and three introns. When we analyzed normal females and males and extra-large male adults, GHRH and PACAP mRNA were found to be predominantly expressed in the brain; the expression levels were highest in normal males. The extra-large males exhibited the lowest mRNA levels of both GHRH and PACAP. Sex differences in GHRH and PACAP mRNA expression during development were also examined in a full-sib family; GHRH and PACAP mRNA were detected at all 27 times sampled from 10 to 410 days old. The GHRH expression levels in females were significantly higher than in males at most of the stages between 20 and 100 days old, while lower than those of males after 120 days old. Five microsatellite loci were identified in GHRH and PACAP genes. We used these five polymorphic markers to genotype 224 individuals, and no significant differences were found between females and males from the Bohai Sea, the Yellow Sea and hatchery samples.

The neutron kinetics of the molten salt reactor is significantly influenced by the fuel salt flow, which leads to the analysis methods for the conventional reactors using solid fuels not being applicable for the molten salt reactors. In this study, a neutron kinetic model considering the fuel salt flow is established based on the neutron diffusion theory, which consists of two-group neutron diffusion equations for the fast and thermal neutron fluxes and six-group balance equations for delayed neutron precursors. The temperature feedback on the neutron kinetics is considered by introducing a heat transfer model in the core, in which the group constants which are dependent on the temperature are calculated by the code DRAGON. The mathematical equations are discretized and numerically calculated by developing a code, in which the fully implicit scheme is adopted for the time-dependent terms, and the power law scheme is for the convection–diffusion terms. The neutron kinetics is conducted during three transient conditions including the rods drop transient, the pump coastdown transient and the inlet temperature drop transient. The relative power changes and the distributions of the temperature, neutron fluxes and delayed neutron precursors under these three different transient conditions are obtained in the study. The results provide some valuable information for the research and design of this new generation reactor.

The molten salt reactor (MSR), which is one of the ‘Generation IV’ concepts, can be used for transmutation, and production of electricity, hydrogen and fissile fuels. In this study, a single-liquid-fueled MSR is designed for conceptual research, in which no solid material is present in the core as moderator, except for the external reflector. The fuel salt flow makes the MSR neutronics different from that of conventional reactors using solid fuels, and couples the flow and heat transfer strongly. Therefore, it is necessary to study the core characteristics with due attention to the coupling among flow, heat transfer and neutronics. The standard turbulent model is adopted to establish the flow and heat transfer model, while the diffusion theory is used for the neutronics model, which consists of two-group neutron diffusion equations for fast and thermal neutron fluxes, and balance equations for six groups of delayed neutron precursors. These two models which are coupled through the temperature and heat source are coded in a microcomputer program. The distributions of the velocity, temperature, neutron fluxes, and delayed neutron precursors under the rated condition are obtained. In addition, the effects of the inflow temperature, inflow velocity, and the fuel salt residence time out of the core are discussed in detail. The results provide some valuable information for the research and design of the new generation molten salt reactors.

The Molten Salt Reactor (MSR) can meet the demand of transmutation and breeding. In this study, theoretical calculation of steady thermal hydraulic characteristics of a graphite-moderated channel type MSR is conducted. The DRAGON code is adopted to calculate the axial and radial power factor firstly. The flow and heat transfer model in the fuel salt and graphite are developed on basis of the fundamental mass, momentum and energy equations. The results show the detailed flow distribution in the core, and the temperature profiles of the fuel salt, inner and outer wall in the nine typical elements along the axial flow direction are also obtained.

This study investigated the biodegradation of nonylphenol (NP) in mangrove sediments collected at five sites along the Tanshui River in northern Taiwan. NP biodegradation rate constants ( k 1 ) and half-lives ( t 1/2 ) ranged from 0.039 to 0.139 day −1 and 5.0 to 17.8 days, respectively. The biodegradation of NP was enhanced by the addition of yeast extract, hydrogen peroxide, brij 35, sodium chloride, or cellulose. However, NP biodegradation was inhibited by the addition of humic acid, heavy metals, or phthalic acid esters (PAEs). Of the microorganism strains isolated from the mangrove sediment, we found that strains A9, A10 and A13 (all identified as Bacillus sp.) expressed the best biodegrading ability. NP biodegradation rate constants ( k 1 ) and half-lives ( t 1/2 ) by the three strains ranged from 0.291 to 0.630 day −1 and 1.1 to 2.4 days, respectively. The highest NP biodegradation rate was found in the sediment with the inoculation containing strains A9, A10 and A13, whereas the sediment without any inoculation had the lowest biodegradation rate.

The bread wheat elasticity, which is very important for bread-making quality, is largely determined by the composition of high-molecular-weight glutenin subunits (HMW-GS). The HMW-GS encoded by Glu-B1 loci are highly polymorphic and the combinations 17+18 and 14+15 are good for bread making. Thus it is very important to identify the alleles at Glu-B1 loci for wheat quality improvement. In this study, the five common HMW-GS types encoded by Glu-B1x locus carried by 18 Chinese bread wheat cultivars (or lines) were analyzed by SDS-PAGE. Two pairs of PCR primers which could distinguish the Glu-Blx alleles of the five common HMW-GS types were designed based on the Glu-B1x gene sequences (Reddy and Appels, 1993; Genbank accession: X13927; Genbank accession:AY367771). 22 recombinant inbred lines (RILs) derived from Jing711 (contains 17 subunit on Glu-B1x) and Pm97034 (contains 14 subunit on Glu-B1x) were used to validate the accuracy of the primers, which showed that the two specific markers could be used together to distinguish alleles at Glu-B1x locus and accelerate wheat quality breeding by marker assisted selection.

Karyopherins, including alpha and beta types, are transport proteins in the eukaryotic cell that carry cargoes across nuclear pore complexes into or out of the nucleus. In this study, full open reading frames of one beta and three alpha types of karyopherin were cloned from cDNA of the domestic silkworm (Bombyx mori). The one beta and three alpha types' open reading frames were 2661, 1563, 1515, and 1551 base pairs long, respectively, and coded 886, 520, 504, and 516 amino acids, respectively. The alphas all had one importin-beta-binding (IBB) domain, and eight, four, or seven armadillo/beta-catenin-like repeats. The beta had 19 HEAT repeat domains, which constructed one importin-beta-N-terminal domain and one IBB domain. The recombinant proteins were expressed in Escherichia coli cells. The molecular weight of the beta type was approximately 100 kDa, and the alphas weighed approximately 60 kDa. Phylogenic tree construction revealed that the alphas could be classified into three known karyopherin-alpha subfamilies. We detected mRNA of the four karyopherins in normal 3rd day of 5th instar larvae, and in larvae injected with Gram-positive bacteria, Gram-negative bacteria, viruses, and fungi using real-time fluorescence quantitative reverse transcriptase-polymerase chain reaction, and found that the four karyopherins were widely distributed, but their expression levels were related to tissues type, the microbe injected, and the time point.

The fictitious stress method (FSM) based on analytical integral of Kelvin’s solutions to calculate displacements or stresses have been proposed by K.Kuriyama. The paper represents the procedure how to use this method to compute stresses and displacements of rocks underground, and a modeling method for tunnel and bolt drilling element. In additional, some roadway with one prestressed bolting is taken as example and plot the Szz component of stress compared with Flac3d result. The FSM which employs integral of Kelvin’s solution as influence coefficients is a calculation method of high accuracy, and the computation time complexity is lower compared with either the finite element method or finite difference method. KEYWORD: fictitious stress method; analytical integrals; triangular leaf elements; BEM International Conference on Industrial Technology and Management Science (ITMS 2015) © 2015. The authors Published by Atlantis Press 1229 where Ul(P) and lm(P) are the displacement and stress components of the plane, and pk, bk are the components of the resultant tractions and body force, and U*lk(P,Q) are the Kelvin’s Solutions.Omitting the body force and the displacement of the rigid, the stress and the displacement of point P can be calculated, viz.

Suspended sediments from large and middle size Chinese estuaries, including the Yalujiang, Shuangtaizihe, Luanhe, Jiaojiang and Zhujiang, were analysed to understand trace metal transport in the coastal zone. The determinations of 13 major and trace elements plus organic carbon were made of total concentrations and were fully validated by certified reference materials (CRMs). The combination of the data sets with other Chinese estuaries, such as Changjiang and Huanghe, provides an overview of particulate trace metal geochemistry in this region. Trace metal levels in Chinese rivers are relatively low compared with those draining industrialized regions of Europe and North America. In the estuaries, most particulate elements illustrate stable distribution in the mixing zone until a salinity of 30, especially when absolute concentrations are normalized to aluminium, although the total suspended matter (TSM) is quite different in time and space. Using Al as a reference, it was estimated that 25–40% for Cu, and 5–20% for Pb could remain in labile part in the Jiaojiang, Shuangtaizihe and Zhujiang, whereas different features of labile elements were found in the Changjiang and Luanhe. The mean enrichment factor (EFm) increases with higher sewage to river runoff ratio (S/R) over the drainage basin and EFm for suspended matter is higher than that for bottom sediments. Finally, inputs of particulate trace metals to the coast are estimated based on the riverine sediment load and chemical compositions.

The Ti40 (Ti–25V–15Cr–0.2Si) alloy is a burn resistant β titanium alloy. Second phase precipitation after high temperature exposure for a long time has been studied. The second phases, i.e. Ti 5 Si 3 and α, precipitate from the β matrix after the Ti40 alloy has been exposed at high temperature for a long time. The Ti 5 Si 3 phase distributes discontinuously along the grain boundary if the exposure temperature is below 540°C. Exposed at 700°C for 100 h, the coarse Ti 5 Si 3 phase rapidly grows, its tensile properties obviously reducing after thermal exposure when conventionally forged. Coarse Ti 5 Si 3 and α phases form after exposure at 540°C for 100 h, which leads to serious decrease of tensile properties after thermal exposure for isothermally forged alloys. Ti 5 Si 3 precipitates distribute discontinuously along grain boundary in the conventionally forged alloys after creep exposure. There are also many coarse rod-like α phases in isothermally forged alloys after creep exposure.

In this paper, we present a new approach to the problem of inverter elimination in domino logic synthesis. A small piece of static CMOS logic is introduced to the circuit to avoid significant area penalty resulting from duplication. To maximize the domino logic part and to minimize the static CMOS logic part, a generalized automatic test pattern generation (ATPG)-based logic transformation is proposed to eliminate or relocate a target inverter. Based on the new concept of dominating set of mandatory assignment (DSMA) and the corresponding implication graph, we propose algorithms to identify a minimum candidate set for a target inverter. Experimental results show that logic transformation based on the implication graph can reduce transistor counts by 25% on average, while the delay increases less than 3%.

To detect cell cross-contamination and verify the origin of the cells of an artificial organ, the sensitive isoenzyme assay was chosen to monitor the quality test of cell-based devices. Authoritative cell evaluation of artificial skin products has been established in this study. Human and porcine cell suspensions with total cell counts of between I x 10 5 and 4 x 10 6 were individually tested to determine the activity of isoenzymes. Human fibroblast, mixed with 1% to 100% of porcine fibroblast, could be significantly distinguished in the isoenzyme assay. Based on the glucose-6-phosphophate-dehydrogenase analysis, the human fibroblast tested in this study belonged to the B type human cells. Lactate dehydrogenase (LD), malate dehydrogenase (MD) and mannose phosphate isomerase isoenzyme (MPI) activities obviously revealed that a different pattern corresponds to the percentage of human and porcine cell mixtures. The discriminatory limit of MPI, LD and MD activity can reach up to 1% of sensitivity of the isoenzyme analysis. This sensitive isoenzyme analysis method allows us to routinely test cellular biomaterials whether interspecies cell line cross-contamination has occurred in the development of artificial organs.

Traditionally, interconnects in multilayer routing technologies have been routed greedily, one at a time. This yields good routings for the first few interconnect trees, but poor routings for the remaining trees. In contrast, we present a new performance-driven approach for layer assignment and routing in which the quality of the routing is largely order independent, minimizing the peak tree delays in the process. We introduce a dynamically adjusted area quota for each tree on each routing layer. This ensures that no tree uses up excessive routing space on the "good" layers. Since the parasitic coupling of different layers varies over a large range, assignment of the edges in the trees to specific routing layers has a large impact on the interconnect delay. Furthermore, we derive an expression for the contribution of an edge in a tree to the total delay of that tree as a function of the layer to which the edge is assigned. We use this expression to introduce a lookahead key for each edge of each tree that enables us to decide whether to route that edge immediately on the current layer or to postpone it to a subsequent layer. Our approach can be used to construct a performance-driven layer assignment and routing algorithm specifically tailored toward any given combination of the timing, routing and technology models. Our experimental results demonstrate that this approach consistently outperforms the multipass greedy scheme currently in vogue, both in worst case delay and in routability.

Much of the previous work on crosstalk minimization attempted to handle crosstalk during the process of routing the nets. However, this necessitates the estimation of the expected crosstalk due to nets that are yet to be routed. In contrast, post-processing algorithms can use accurate crosstalk measurements to respace the wires, thus improving the crosstalk even in routings produced by crosstalk-aware routers. However, the postprocessing algorithms presented so far have been restricted either by the use of a gridded model or by the difficulty of optimizing the highly nonlinear crosstalk-based objective functions. We address the problem of minimizing the peak crosstalk in a routed region by respacing its critical nets and their neighbors. We study the variation of the crosstalk in a net and its neighbors when one of its trunks is perturbed, showing that the trunk's perturbation range can be efficiently divided into subintervals having monotonic or unimodal crosstalk variation. This result enables us to determine the optimum location for the trunk without needing to solve any nonlinear equations. Using this, we construct an algorithm to minimize the peak crosstalk in the nets of a gridless channel. Although we present our results in terms of channel routing, our theory is also applicable to more general routing models. Furthermore, our crosstalk model subsumes the models used in most prior works on noise-aware routing. Our experiments verify the effectiveness of our approach.