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71.
The objective of this study was to develop equations to predict carcass tissue weights and percentages and boneless carcass non-trimmed cut weights by using the cold carcass weight (CCW) and three other traits at the 6–7th rib section, which are routinely collected in carcass markets in Japan. Carcasses from 94 Japanese Black steers were used for the multiple regression analysis with a stepwise procedure and a novel Least Absolute Shrinkage and Selection Operator (LASSO). The accuracies of prediction (R2) and RMSEs for the carcass tissue and cut weights were similar between the two procedures. In contrast, LASSO appeared to be the better procedure for predicting carcass tissue percentages. The longissimus muscle area and subcutaneous fat thickness were the important predictors for the lean percentage in the stepwise procedure, and CCW was additionally selected when the LASSO procedure was used.  相似文献   
72.
73.
The effect of CeO2 loading amount of Ru/CeO2/Al2O3 on CO2 methanation activity and CH4 selectivity was studied. The CO2 reaction rate was increased by adding CeO2 to Ru/Al2O3, and the order of CO2 reaction rate at 250 °C is Ru/30%CeO2/Al2O3 > Ru/60%CeO2/Al2O3 > Ru/CeO2 > Ru/Al2O3. With a decrease in CeO2 loading of Ru/CeO2/Al2O3 from 98% to 30%, partial reduction of CeO2 surface was promoted and the specific surface area was enlarged. Furthermore, it was observed using FTIR technique that intermediates of CO2 methanation, such as formate and carbonate species, reacted with H2 faster over Ru/30%CeO2/Al2O3 and Ru/CeO2 than over Ru/Al2O3. These could result in the high CO2 reaction rate over CeO2-containing catalysts. As for the selectivity to CH4, Ru/30%CeO2/Al2O3 exhibited high CH4 selectivity compared with Ru/CeO2, due to prompt CO conversion into CH4 over Ru/30%CeO2/Al2O3.  相似文献   
74.
75.
Powders and pellets of new NASICON compositions have been synthesized using a mixed inorganic-organic sol-gel synthesis, by the preliminary formation of a pre-hydrolized TEOS xerogel. The investigated compositions can be described by the general formula Na3Zr2-(x/4)Si2-xP1+xO12, obtained by keeping the Na concentration constant (= 3) at the optimum value reported for ionic conductivity, with x = 0 (the usual NASICON composition), 0.667, and 1.333. The xerogels were calcined at various temperatures in the range 400–1200°C. The powder samples were analyzed by TG/DTA, BET measurements, XRD, and SEM. The powders calcined at 500°C were sintered into pellets at 1100°C for 6 h. The sintering behavior of the pellets was investigated by dilatometric measurements and SEM observations. The sinterability increased with increasing x value. Dense samples of the new compositions were obtained by sintering at only 1100°C. This is attributed to the occurrence of liquid phase sintering. The electrical conductivity of the NASICON sintered bodies was measured by ac impedance spectroscopy. The conductivity decreased with decreasing c0 lattice parameter of the hexagonal structure or increasing x value. The CO2 gas sensors, using as electrolyte the dense samples of the new NASICON compositions, showed good EMF response that was very close to the theoretical value, even for the sample with x = 1.333 that showed much lower conductivity.  相似文献   
76.
The distributions of the number of molecules per cluster (cluster size) of ethanol cluster ion beams were measured by the time-of-flight method. The cluster sizes at the peak and minimum tail (minimum size) of the distribution increased with increase of the retarding voltage. A difference appeared between the measured minimum size and the calculated values using a formula based on the early measurements on the velocity distributions of gas clusters.  相似文献   
77.
The effect of power interchange operation of multiple household gas engine cogeneration systems (H-GCGS) on the energy-saving is investigated using an optimization approach based on the mixed-integer linear programming. In this power interchange operation, electricity generated by H-GCGS is shared among households in a housing complex without transmitting to a commercial electric power system so that the operating time of these systems may increase. This paper numerically analyzes optimal operational strategies for 20 households and three types of household energy supply configurations: the power interchange operation of the H-GCGSs (IC), stand-alone operation of each H-GCGSs (SA), and conventional energy supply system without the H-GCGSs. A numerical result clarifies the effectiveness of the power interchange operation from the energy-saving viewpoint and a dominant parameter for evaluating the energy-saving effect.  相似文献   
78.
The prorenin/renin receptor ((P)RR) is a multifunctional protein that is widely distributed in various organs. Despite intensive research for more than 20 years, this receptor has not been fully characterized. In this study, we generated mice overexpressing the tubular epithelial (P)RR gene ((P)RR-TG mice) to test the previously reported functional role of (P)RR by Ramkumar et al. in 2015 using tubular specific (P)RR KO mice. (P)RR-TG mice were maintained and analyzed in individual metabolic cages and were administered angiotensin II blocker (ARB), direct renin inhibitor (DRI), and bafilomycin, that is, vacuolar ATPase (V-ATPase) antagonist. (P)RR-TG mice were hypertensive and had alkalized urine with lower osmolality and Na+ excretion. ARB and DRI, but not bafilomycin, concurrently decreased blood pressure. Bafilomycin acidized urine of (P)RR-TG mice, or equivalently this phenomenon restored the effect of overexpressed transgene, suggesting that (P)RR functioned as a V-ATPase in renal tubules. Afterall, (P)RR-TG mice were mated with alternative renin transgenic mice (ARen2-TG), which we identified as intracellular renin previously, to generate double transgenic mice (DT-TG). Lethal renal tubular damage was observed in DT-TG mice, suggesting that intracellular renin may be a ligand for (P)RR in tubules. In summary, (P)RR did not substantially affect the tissue renin-angiotensin system (RAS) in our model of tubular specific (P)RR gene over-expression, but alternative intracellular renin may be involved in (P)RR signaling in addition to conventional V-ATPase function. Further investigations are warranted.  相似文献   
79.
We prepared polycrystalline pellets of (U,Y)O2, containing YO1.5 up to 11 mol.%. We performed indentation tests on the pellets, and evaluated the Young’s modulus and hardness. We measured the heat capacity and the thermal diffusivity, and evaluated the thermal conductivity. We succeeded in evaluating the effect of Y content on the thermophysical properties of (U,Y)O2. We revealed that the Young’s modulus, hardness, and thermal conductivity of (U,Y)O2 decreased with increasing the Y content.  相似文献   
80.
野外试验场黄土的理化分析   总被引:13,自引:6,他引:7  
本实验为低,中水平放射性废物浅地层处置安全评价提供现场土壤的物理化学参数。采样深度在0.5-9.1m范围内,每个样品进行10项测定;矿物组成,粒度分布、密度、总孔隙度、有效孔隙度、给水度、持水度、渗透系数、阳离子交换容量、含水量。  相似文献   
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