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A two-step joining approach was proposed to minimize or eliminate decomposition bubbles in laser joining metal to polymer. Finite element simulation was utilized to analyze the temperature distribution and incorporated the bubble shrinkage mechanism and thermal capillary effect, providing the theoretical basis for explaining the reduction in bubbles and their movement. Two experimental setups were employed: with and without laser beam offset. In experiments without offset, the bubbles after the second joining process underwent significant shrinkage, resulting in a notable reduction in volume. In offset experiments, the bubbles not only reduced in size but also exhibited movement and elimination. This was induced by the laser beam offset, which created a temperature gradient perpendicular to the joining direction, triggering thermal capillary effects that caused the bubbles to migrate towards the hotter side and eventually escape from the joint edges. Consequently, the joints obtained through double welding exhibited higher fracture stress as compared to those obtained through single welding. The theoretical analysis of the bubble reduction mechanism aligned with experimental observations, further validated by camera images.

Dendrobium williamsonii and Dendrobium cariniferum (Orchidaceae) are endangered perennial herbs, and they are very similar in morphology. Chloroplast genome sequencing technology provides a powerful tool for molecular analysis to get more infomation for phylogenetic analysis and identification of Dendrobium species. In this study, the complete chloroplast genomes of Dendrobium williamsonii and Dendrobium cariniferum were assembled and characterized using Illumina NovaSeq 6000. The genome sizes are 159 695 and 159 479 bp, including pairs of inverted repeats (27 055 and 27 024 bp) each separated by small single-copy regions (18 451 and 18 488 bp) and large single-copy regions (87 134 and 86 943 bp). The chloroplast genome overall GC content was 37.11% and 37.13%, respectively. Each chloroplast genome encoded the same number (147) of genes, including 88 protein-coding genes, 51 tRNA genes, and 8 rRNA genes. Comparative analysis of chloroplast genomes revealed the high degree of divergence included accD-psaL and ycf4 -cemA. The phylogenetic tree showed the two Dendrobium species formed only one small clade. A pair of primers that could effectively identify the two Dendrobium species were also screened. This study will provide theoretical basis for species identification, genetic breeding, and evolution of Dendrobium.

A new method, namely the improved quantum molecular dynamics model incorporated with the microscopic potential energy surface, is proposed to simulate the dynamical evolution from saddle to scission point and to calculate the isotope yields of fission fragments in thermal neutron-induced fission of actinide nuclei near 236U. With this approach, the shell and pairing effects are introduced by the microscopic potential energy, while the isospin effect, the dynamical effects of fluctuations and correlations in fission process are automatically included in the improved quantum molecular dynamics model. These two aspects eventually influence the productions of fission fragments. The calculated both charge and mass distributions of fission fragments for a series of actinide nuclei are in overall agreement with the evaluated data from JEFF-3.3 and ENDF/B-VIII.0. The isotope distributions of fission fragments in the fission of 236U reproduce the data reasonable well, from which we extract the relationship between peak mass number of the isotope distributions and the charge number of fission fragments. We find that this relationship deviates linear relation slightly at certain cases, which indicates the isospin nonequilibrium effect. By tracking back to the fission process on the two dimension plane of elongation and mass asymmetry of prefragments, we find that the necked-in shape and the separation of two parts happen much faster for the 132Sn than 128,136Sn in the time evolution of the distance R between the centers of two parts of the fissioning system. The events producing 128,132,136Sn and 136,140,144Xe present two kinds of average fission paths with bypassing and going through the minimum-energy valley of the microscopic potential energy surface, respectively.

Particle and heat fluxes were successfully controlled by using a continuously flowing liquid Li (FLiLi) limiter in the H-mode discharges with high plasma heating power in the Experimental Advanced Superconducting Tokamak device. There were strong interactions between the FLiLi limiter and high-power plasma with a ∼ 8.3 MW source heating power, and successively, a bright Li radiation ring was produced, which effectively decreased fuel particle recycling by approximately 50%. Due to Li efflux from FLiLi during a series of high-power discharges, an obvious real-time wall conditioning effect was produced, and fuel particle recycling further decreased. Moreover, the value of Zeff decreased from 2.3 to 1.6 due to a decrease in impurity sources; this was attributed to the accumulation of Li deposited on the first wall, which effectively protected the wall materials. The decreased recycling and impurity radiation achieved high-energy confinement plasma, and the average stored energy increased up to ∼ 290 kJ. Moreover, due to the effect of Li vapor shielding, nearly 30% plasma heat flux was dissipated before it arrived at the Li limiter. These results promote further exploration of liquid Li solutions for the critical challenge of heat flux handling and particle control in fusion power plants.

A significant change in the background ELM behavior prior to neon (Ne) seeding has been observed in a series of repetitive radiative divertor experiments in EAST. With similar operational parameters, the ELM behavior before Ne seeding changes from large to mixed ELMs, and finally evolves to pure small ELMs. Meanwhile, a significant increase in both Ne and high-Z impurity (W and Mo) emissions has been observed in the bulk plasma, suggesting the retention and recycling of Ne impurity from the wall surface. Experimental results show that the variation in background ELM behavior is highly correlated with the occurrence of high-Z impurity accumulation. The increased accumulation of high-Z impurities leads to a lower electron temperature both in the plasma core and edge, accompanied by a higher and more peaked electron density in the plasma core. Pedestal linear stability analysis reveals that the decreased pedestal electron temperature and thus the lower pressure gradient and lower edge current density are the primary reason for the change of background ELM behavior. The concentration of recycling Ne in the bulk plasma is estimated to be ∼1% in the discharges with pure small ELMs.

ABSTRACT: Cottonseed meal (CSM), which is an unconventional protein material with abundant sources, high protein content, and a relatively cheap price, can be used in poultry diets. The aim of this study was to investigate the effects of CSM on slaughter performance, meat quality and meat chemical composition in Jiangnan White goslings. A total of 300 healthy 28-day-old male goslings were randomly divided into 5 treatments, with 6 pens containing 10 geese each. Five isonitrogenous and isocaloric experimental diets were formulated such that 0% (a corn-soybean meal basal diet, control), 25% (CSM25), 50% (CSM50), 75% (CSM75), and 100% (CSM100) protein from soybean meal was replaced with CSM (corresponding to 0, 6.73, 13.46, 20.18, and 26.91% CSM in the feed, respectively). On day 70, 1 goose from each pen (6 geese per treatment) was randomly selected and killed to measure the slaughter performance, meat quality, and the meat amino acid (AA) and fatty acid (FA) compositions. The results showed that dietary CSM did not affect the slaughter performance or meat quality of geese (P > 0.05). The fat content of breast muscle in the CSM100 group was higher than that in the control group (P < 0.05). A concentration of 13.46% or more dietary CSM increased the threonine content but decreased the cysteine content, and 20.18% dietary CSM also decreased the valine content (P < 0.05). Dietary CSM concentration had no effect on the content of total saturated FAs (SFAs, P > 0.05), but 20.18 and 26.91% dietary CSM increased the content of total monounsaturated FAs and decreased the content of total polyunsaturated FAs (PUFAs) and PUFA/SFA in the breast muscle of geese (P < 0.05). In conclusion, dietary CSM did not affect the slaughter performance or meat quality of geese, but the replacement of soybean meal with CSM in whole or high proportion altered the composition of AAs and FAs in breast muscle.

ABSTRACT: This study was conducted to investigate the effects of lycopene (LYC) on mitochondrial oxidative injury and dysfunction in the liver of aflatoxin B1 (AFB1)-exposed broilers. A total of 192 healthy 1-day-old male broilers were randomly divided into 3 groups with 8 replicates of 8 birds each. Birds in the 3 groups were fed basal diet (control), basal diet with 100 µg/kg AFB1, and basal diet with 100 µg/kg AFB1 and 200 mg/kg LYC, respectively. The experiment lasted 42 d. The results showed that AFB1 decreased average daily body weight gain (ADG), average daily feed intake, and gain to feed ratio (G :F) compared to the control group, the LYC supplementation increased ADG and G/F compared to AFB1 group (P < 0.05). Broilers in the AFB1 group had lower mitochondrial glutathione (mGSH) concentration and glutathione peroxidase (GSH-Px), manganese superoxide dismutase (MnSOD), and thioredoxin reductase activities, and higher hydrogen peroxide (H2O2) and reactive oxygen species (ROS) concentrations than the control group (P < 0.05). The LYC increased mGSH concentration and GSH-Px and MnSOD activities, and decreased H2O2 and ROS concentrations compared to AFB1 group (P < 0.05). Broilers fed the AFB1 diet showed increased mitochondrial swelling and decreased adenosine triphosphate concentration than the control group, and LYC had opposite effects (P < 0.05). The AFB1 decreased the activities of mitochondrial electron transfer chain (ETC) complexes I, II, III, and V, downregulated the mRNA expression levels of hepatic MnSOD, thioredoxin 2, thioredoxin reductase, peroxiredoxin-3, peroxisome proliferator-activated receptor γ coactivator 1α, nuclear respiratory factor 1, and mitochondrial transcription factor A compared with the control group (P < 0.05), and LYC increased activities of mitochondrial ETC complexes III and V, and upregulated mRNA expression levels of these genes in comparison to AFB1 group (P < 0.05). In conclusion, the LYC protected broilers from AFB1-induced liver mitochondrial oxidative injury and dysfunction by stimulating mitochondrial antioxidant capacity and maintaining mitochondrial biogenesis.

EAST tokamak has been equipped with upper tungsten divertor since 2014. The tungsten accumulation has been often observed in NBI-heated H-mode discharges suggesting deleterious tungsten confinement in the plasma core. It causes not only H-L back transition but also plasma disruption in several discharges. Suppression of the tungsten accumulation is therefore the most important issue in EAST to achieve a long pulse H-mode discharge. In order to study the tungsten behavior in the long pulse discharge, tungsten spectra have been measured at 20–140Å. The tungsten density, nw, is evaluated from the intensity of tungsten unresolved transition array (W-UTA) in a wavelength range of 45–70Å which is composed of several ionization stages of tungsten, e.g. W27+-W45+ at Te0∼2.5keV). It is found that the tungsten accumulation can be suppressed when the 4.6GHz LHW with PLHW∼0.8MW is superimposed on the NBI phase (PNBI= 1.9MW). During the superimposed phase the ELM frequency, fELM, increases from ∼30Hz to ∼60Hz and the tungsten density is halved compared to the NBI-heated discharge. The H-mode discharge can be thus steadily sustained for longer period. It is found that the nw is a large function of the ratio of LHW power to the total injection power, PLHW/(PLHW+PNBI), and the nw can be reduced, at least, in an order of magnitude smaller than that in NBI-heated discharges at PLHW/(PLHW+PNBI)≥0.8. The result strongly suggests a possible way toward the steady H-mode discharge. Keywords: EAST, Tungsten divertor, Tungsten spectrum, ELMy H-mode, Impurity accumulation

The passively Q-switched laser oscillation from an unprocessed Nd:La[B.sub.3][O.sub.6] cleavage microchip with a [Cr.sup.4+]:YAG saturable absorber in an end-pumped plano-plano resonator is described. The polarization and spectral properties of the laser radiation are measured and the results have shown that the unprocessed Nd:LaBO cleavage microchip is a good gain medium for the passively Q-switched microchip lasers.

The study present the results of incorporating N into self-assembled InAs quantum dots (QDs) capped with an InGaAs cap layer. Experimental results indicate that such incorporation can redshift the QD ground state and decrease the energy spacing between the QD ground and first excited states.

The improvement of the laser performances of an unprocessed Nd(super 3+) is to LaB3O6 (LaBO) cleavage microchip with higher Nd(super 3+) concentration in an end-pumped plano-plano resonator are investigated. The results show that the cleavage technique can become a practical and effective method to obtain the high-quality microchip laser medium easily and directly.

A fuzzy neural network system (FNSS) is proposed for implementing fuzzy inference systems for system modeling. The use of fuzzy similarity measure helps to eliminate redundant fuzzy rules. This reduces the complexity of the network and makes it suitable for industrial applications. Computer simulation studies indicate a satisfactory performance of FNSS. A novel and efficient on-line initialization method is also designed for selecting the initial parameters of the FNNS.

NbN/AlN/NbN junctions or AlN/NbN bilayers are prepared on single crystal MgO (001) or MgO(111) substrates using direct current or radio frequency magnetron sputtering techniques. It is reported that the AlN barrier in NbN/AlN/NbN/MgO (001) is amorphous while the NbN/AlN/NbN/MgO (111) is single-crystalline with (001) orientation.