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A mechanism coupling the stimulated Brillouin scattering (SBS) of two-color lasers with wavelengths of 527 and 351 $\mathrm{nm}$ via the two-ion decay instability is proposed. When the SBS reflectivities of both lasers exceed 10%, the ion-acoustic wave excited by the 527 $\mathrm{nm}$ laser seeds the decay process of the ion-acoustic wave excited by the 351 $\mathrm{nm}$ laser, thereby promoting the decay of the latter into the former. This results in a significant reduction in the SBS reflectivity of the 351 $\mathrm{nm}$ laser, while the SBS of the 527 $\mathrm{nm}$ laser exhibits minimal variation, consequently reducing the total SBS reflectivity. The total SBS reflectivity initially decreases and then increases as the intensity fraction α of the 527 $\mathrm{nm}$ laser rises. When $\alpha \sim (20\%{-}30\%)$ , the laser energy reflections from both lasers become approximately equal, achieving the minimum total reflectivity. Through this mechanism, the incidence of the two-color lasers can achieve lower reflected energy compared to monochromatic lasers with the same total intensity. These results demonstrate the significant potential of replacing a small fraction of high-frequency light with low-frequency light in enhancing the laser-target coupling efficiency for inertial fusion energy.

We hypothesised that adding a combination of fibrolytic and amylolytic enzymes to the diet of early-lactation dairy cows would improve rumen enzyme activity and bacterial diversity, promote energy metabolism, and benefit milk production in cows. Twenty multiparous early-lactation (90 ± 5 d) Holstein cows with similar body conditions were randomly allocated to control (CON, n = 10) and experimental (EXP, n = 10) groups in a completely randomised single-factor design. The CON was fed only a basal total mixed ration diet, and the diet of the EXP was supplemented with a combination of fibrolytic and amylolytic enzymes at 70 g/cow/d (cellulase 3 500 CU/g, xylanase 2 000 XU/g, β-glucanase 17 500 GU/g, and amylase 37 000 AU/g). The experiment lasted 28 days, with 21 days for adaptation and 7 days for sampling. Enzyme addition increased the activity levels of α-amylase and xylanase, and the ammonia-N concentration (P 0.1%) or genus (richness > 1%) composition between the CON and EXP groups (P > 0.05). A tendency of difference was found between CON and EXP (R = 0.22, P = 0.098) in principal component analysis. Ten genera showed different abundances across the CON and EXP groups (linear discriminant analysis effect size, linear discriminant analysis > 2). EXP increased the ratio of albumin to globulin and the concentrations of total cholesterol and low-density lipoprotein cholesterol (P

Information technology has received a wide range of applications in agriculture industry to improve production environment and reduce resource costs. This article introduces the agricultural collection system of ARM Company, which uses S3C2440 as its control core and takes zigbee as its wireless transmission. This system achieves the collection and processing of information like illumination intensity, CO2 concentration, soil temperature and humidity and geographic position. This article also gives the introduction to the main hardware and software design. It has been proved by experiments that the data collected is accurate and the working condition is stable and thus this system receives a wide range of applications in agriculture industry.

The objectives of this study were to determine true phosphorus (P) digestibility, degradability of phytate-P complex and the endogenous P outputs associated with brown rice feeding in weanling pigs by using the simple linear regression analysis technique. Six barrows with an average initial body weight of 12.5 kg were fitted with a T-cannula and fed six diets according to a 6 × 6 Latin-square design. Six maize starch-based diets, containing six levels of P at 0.80, 1.36, 1.93, 2.49, 3.04, and 3.61 g/kg per kg dry-matter (DM) intake (DMI), were formulated with brown rice. Each experimental period lasted 10 days. After a 7-day adaptation, all faecal samples were collected on days 8 and 9. Ileal digesta samples were collected for a total of 24 h on day 10. The apparent ileal and faecal P digestibility values of brown rice were affected ( P 0.05) in true P digestibility values (57.7 ± 5.4 v. 58.2 ± 5.9%), phytate P degradability (76.4 ± 6.7 v. 79.0 ± 4.4%) and the endogenous P outputs (0.812 ± 0..096 v. 0.725 ± 0.083 g/kg DMI) between the ileal and the faecal levels. The endogenous faecal P output represented 14 and 25% of the National Research Council (1998) recommended daily total and available P requirements in the weanling pig, respectively. About 58% of the total P in brown rice could be digested and absorbed by the weanling pig. Our results suggest that the large intestine of the weanling pigs does not play a significant role in the digestion of P in brown rice. Diet formulation on the basis of total or apparent P digestibility with brown rice may lead to P overfeeding and excessive P excretion in pigs.

An analytical model to evaluate the magnetic forces in permanent magnet brushless dc motor with rotor eccentricity is presented. The calculated magnetic forces obtained from the model are found to agree well with those obtained from numerical simulations that are very computationally demanding.

The transition of the internal structure in microwave chemical-vapor-deposited carbon nanotubes (CNT) is investigated using scanning electron microscopy and high-resolution transmission electron microscopy. A growth model based on surface and bulk diffusions of carbon into and/or onto the Fe catalyst surface is used to describe the hollow to bamboo transition in nanotubes.

An effective approach of characterizing and optimizing the differential impedance and crosstalk of head interconnect is shown. Applying robust design technique, the cross talk is optimized and it is found that there is less variation caused by uncontrollable sources, compared to original design.

An analytical solution for the write field distribution in perpendicular recording system is presented. The effect of the soft underlayer on the write field is studied to provide guidelines for the perpendicular recording head design.

Theoretical and numerical studies on stimulated Raman scattering (SRS) and two-plasmon decay (TPD) with parameters ranging from a direct-drive scheme to shock ignition are presented. A transition from the TPD-dominant regime, through TPD with strong pump depletion, to the SRS-dominant regime shows that SRS is becoming increasingly significant under ignition conditions. Theoretically, we present an envelope model for both SRS and TPD in inhomogeneous plasmas with density not very close to quarter-critical density and analyze a highly nonlinear regime of TPD where the compression of Langmuir waves occurs. However, as the convective threshold for SRS is surpassed, low-density SRS itself controlled by filamentation can dramatically suppress high-density TPD. These physical changes are well described by two-dimensional particle-in-cell simulations. In addition, scalings of hot-electron fraction and reflectivities also indicate such a transition process, and qualitatively agree with recent experiments. [ABSTRACT FROM AUTHOR]