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91.
2009年2月3日,春节长假刚过,太阳纸业和美国国际纸业巨资联袂打造的年产40万吨无菌液体食品包装纸生产线又正式开机,排满了的订单令这台世界一流的机台又恢复了忙碌和生机.此前,这个机台曾饱受因.三聚氰胺"事件引起的乳业市场下滑的影响,之后又逢国际金融风暴造成的纸业市场萎缩.双重因素的叠加共振,使得这一被寄于厚望的项目自2008年8月初投产以来,开开停停了数次.  相似文献   
92.
Patatin-like phospholipase domain-containing protein 3 (PNPLA3), commonly known as adiponutrin, is part of a novel subfamily of triglyceride lipase enzymes with potential effects on triglyceride metabolism in adipose and hepatic tissues. The predicted bovine PNPLA3 sequence has been identified, but expression of the gene had not been examined. The objectives of this study were to confirm the predicted bovine PNPLA3 gene sequence, determine expression of the bovine PNPLA3 gene in response to whole-animal energy balance, identify single nucleotide polymorphisms present in dairy cows, and verify the presence of the protein in the liver. Using liver biopsy samples collected from cows at +28 d relative to calving (DRTC), RNA was isolated and used to generate a cDNA template for amplification of the entire predicted coding sequence of PNPLA3 via PCR. To determine if energy balance alters the expression of PNPLA3, RNA was isolated and mRNA expression quantified in liver samples from mid-lactation cows after a 5-d ad libitum period (n = 5) and after a subsequent 5-d 50% feed restriction period (n = 5), and in samples collected from cows at −14, +1, +14, and +28 DRTC (n = 16). The presence of PNPLA3 protein was detected by Western blot in liver protein samples collected at +28 DRTC. Expression of hepatic PNPLA3 was decreased after a period of feed restriction (8.14 vs. 1.08 ± 2.17 arbitrary units, ad libitum vs. fasted). Expression of PNPLA3 mRNA was decreased at +1 and +14 DRTC compared with −14 DRTC (23.35, 7.28, 10.17, and 14.5 ± 4.9 arbitrary units, −14, +1, +14, and +28 DRTC, respectively). The presence of PNPLA3 protein was detected as a 55-kDa band in hepatic protein isolations from liver tissue collected at +28 DRTC. These data confirm the presence and sequence of the bovine hepatic PNPLA3 gene and single nucleotide polymorphisms. Furthermore, these data indicate responsiveness of bovine hepatic PNPLA3 to energy balance.  相似文献   
93.
The current study was undertaken to investigate the effect of feeding diets varying in sugar concentration to postpartum transition cows on productivity, ruminal fermentation, and nutrient digestibility. We hypothesized that the high-sugar diet would increase dry matter intake and lactation performance. The secondary objective was to characterize changes in ruminal fermentation and nutrient digestibility over the first 4 wk of lactation. Fifty-two Holstein cows, including 28 primiparous and 24 multiparous cows, 10 of which were previously fitted with a ruminal cannula, were assigned to the experimental diets containing either high sugar (HS = 8.4%) or low sugar (LS = 4.7%) immediately after calving, based on their expected calving date. Data and samples were collected on d 5.2 ± 0.3, 12.2 ± 0.3, 19.2 ± 0.3, and 26.1 ± 0.3 relative to parturition for wk 1, 2, 3, and 4 respectively. Cows fed HS had increased dry matter intake compared with those fed LS (18.3. vs. 17.2 kg/d). Further, cows fed HS sorted for particles retained on the pan of the Penn State Particle Size Separator to a greater extent than cows fed LS. Feeding HS tended to increase nadir (5.62 vs. 5.42), mean (6.21 vs. 6.06), and maximum pH (6.83 vs. 6.65). The duration (h/d) and area (pH × min/d) that ruminal pH was below pH 5.8 were not affected by treatment. Ruminal volatile fatty acid concentration and molar proportions of individual volatile fatty acids were not affected by treatment. The digestibility of dry matter, organic matter, neutral detergent fiber, and starch were not affected by treatment, averaging 63.3, 65.2, 43.2, and 93.5%, respectively. Feeding HS decreased plasma glucose concentration compared with feeding LS (51.3 vs. 54.0 mg/dL), but concentration of plasma insulin was not affected by treatment, averaging 4.17 μIU/mL. Cows fed HS had higher concentrations of plasma β-hydroxybutrate (17.5 vs. 10.5 mg/dL) and nonesterified fatty acids (344 vs. 280 μEq/L). Milk yield and milk composition were not affected by treatment, but a tendency for increased milk fat yield was observed for cows fed HS compared with LS (1.44 vs. 1.35 kg/d). The results of the current study imply that replacing cracked corn grain with sucrose may improve dry matter intake, ruminal pH status, and lactation performance.  相似文献   
94.
Mango powders were obtained at water content below 0.05 kg water/kg dry solids using Refractance Window® (RW) drying, freeze drying (FD), drum drying (DD), and spray drying (SD). The spray-dried powder was produced with the aid of maltodextrin (DE = 10). The chosen drying methods provided wide variations in residence time, from seconds (in SD) to over 30 h (in FD), and in product temperatures, from 20 °C (in FD) to 105 °C (in DD). The colors of RW-dried mango powder and reconstituted mango puree were comparable to the freeze-dried products, but were significantly different from drum-dried (darker), and spray-dried (lighter) counterparts. The bulk densities of drum and RW-dried mango powders were higher than freeze-dried and spray-dried powders. There were no significant differences (P ? 0.05) between RW and freeze-dried powders in terms of solubility and hygroscopicity. The glass transition temperature of RW-, freeze-, drum- and spray-dried mango powders were not significantly different (P ? 0.05). The dried powders exhibited amorphous structures as evidenced by the X-ray diffractograms. The microstructure of RW-dried mango powder was smooth and flaky with uniform thickness. Particles of freeze-dried mango powder were more porous compared to the other three products. Drum-dried material exhibited irregular morphology with sharp edges, while spray-dried mango powder had a spherical shape. The study concludes that RW drying can produce mango powder with quality comparable to that obtained via freeze drying, and better than the drum and spray-dried mango powders.  相似文献   
95.
The strong nonlinear interactions between underwater explosion and water surface were numerically investigated using a phase transition model based on a four-equation system,which can deal with the complex deformable interface among different phases,including water,air,explosion bubble,and cavitation.The numerical method is verified by comparing the numerical results with experimental results,and good agreements are found.This study considers an ideal sine wave for simulating the shape of water surface.Two examples of different detonation depths of charge are investigated.In each example,the first case is the basic simulation without surface wave,and the other three cases are the simulations with sine waves of different wavelengths.Unique characteristics of the interactions,such as shock wave propagation,explosion bubble expansion,and the generation,development,and collapse of cavitation,are observed in the numerical simulations.By capturing the detailed density and pressure contours during the interaction process,we can better understand the underlying mechanisms of the explosion bubble,cavitation,and surface waves.These numerical results demonstrate that geometric nonlinearity impacts cavitation evolution and the explosion bubble movement mechanism.Additionally,the secondary cavitation phenomenon has been found in the cases without surface wave,and its fundamental physical mechanism is presented in detail.The present results can expand the existing database of multiphase flow in the underwater explosion and provide an insight into the strong nonlinear interaction between the underwater explosion and water surface.  相似文献   
96.
刘庆亮  何冰  李斌 《红水河》2000,19(2):14-17
采用三维线弹性有限元法,研究了小浪底水利枢纽孔板洞中闸室段在内压和外压作用下围岩、衬砌混缔造 应力和变位。通过对比分析,找出了结构设计的控制条件,并对通气孔的存在给结构带来的影响和中闸室的整体稳定等问题作出了评价。  相似文献   
97.
    
The size of nano particles of ferrites synthesized using low-temperature procedures is sensitive to the chemical reactions. At times, the intermediary stages of chemical reactions remain subtle. It is because of the rate of reactions being fast. Some chemicals which take part in the reaction are playing an autocatalytic role. The understanding of the role played by such reactants is essential for having the control on the reaction and growth size of the particles of the product. FTIR spectroscopic analysis along with DTA can play still a substantial role in the synthesis of nano particles. In this article, the successful use of sol-gel technique with citric acid as the catalysis is analyzed using FTIR and TGA. The individual stages of reaction are explained.  相似文献   
98.
    
Powders of K0.5Na0.5NbO3 (KNN) were prepared by the Polymerized Complex Method (PC method), based on the Pechini-type reaction route. The crystallization process of KNN during the calcination of an amorphous precursor was observed, using TG-DSC analysis and X-ray powder diffraction. After calcination the powders were ball milled, pressed into pellets, and sintered at 1100°C, which is lower than the sintered temperature of the conventional solid-state method. Using this procedure, we achieved relatively high-density and very homogeneous KNN ceramics. The electric properties of the ceramics were investigated. The results showed that these values are superior to those of sintered KNN ceramic counterparts made by the conventional solid-state method.  相似文献   
99.
蒙脱石复合贮热材料的制备   总被引:10,自引:0,他引:10       下载免费PDF全文
蒙脱石是一种层状硅酸盐矿物。本文利用季铵盐与蒙脱石进行阳离子交换反应合成有机蒙脱石 ,然后 ,采用熔融法制备新戊二醇 (NPG)与蒙脱石的复合贮热材料 ,并用 X射线衍射、IR和 DSC等手段研究了复合材料的结构和性能。  相似文献   
100.
    
The unresolved transition array(UTA) simulation with configuration average approximation is used to calculate the spectral properties of plasmas involving complex ions.This method is used to simulate the transmission of X-rays through aluminum plasma and niobium plasma respectively.The results are compared with experiments and other results of advanced models and good agreements are obtained.  相似文献   
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