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51.
The main goal of the present study was to evaluate the long-term effects of a perinatal palatable high-fat diet on the food intake and cholesterol profile of adult rats. Male Wistar rats (aged 22 days) were divided into two groups according to their mother’s diet during gestation and lactation (C p, n = 10; pups from control mothers; and HLp n = 10; pups from mothers fed a palatable high-fat diet). At the 76th day, pups were housed individually for 14 days, and daily food consumption was determined during a period of 6 days. Blood from 100-day-old rats was sampled by cardiac puncture. Fasting (12 h) serum glucose, total cholesterol, LDL-C, HDL-C, triglycerides (TG), and VLDL-C levels were determined. The measurement of food intake was higher in the animals submitted to a hyperlipidic diet during the perinatal period. Serum total cholesterol, LDL-C, HDL-C, TG, VLDL-C and glycemia were increased in the HLp group compared to the control group. Our findings show that an early life environment with a high-fat diet can contribute to metabolic disease in later life.  相似文献   
52.
Laser ablation of solids in liquids technique has been used to obtain colloidal nanoparticles from biological hydroxylapatite using pulsed as well as a continuous wave (CW) laser. Transmission electron microscopy (TEM) measurements revealed the formation of spherical particles with size distribution ranging from few nanometers to hundred nanometers and irregular submicronic particles. High resolution TEM showed that particles obtained by the use of pulsed laser were crystalline, while those obtained by the use of CW laser were amorphous. The shape and size of particles are consistent with the explosive ejection as formation mechanism.  相似文献   
53.
针对恶意程序使用反虚拟执行技术,分析人员在虚拟环境中不能检测到恶意行为的问题,提出了基于关键点复用的恶意行为检测方法.首先通过静态分析,检测程序中的反虚拟执行关键点;提取程序动态运行时调用的API函数,并在程序运行至关键点时创建当前快照;最后,当运行至路径结束点时通过关键点复用运行另一路径.实验结果表明,该方法能有效对抗恶意程序采用的反虚拟执行技术,从而检测恶意行为.  相似文献   
54.
孟加拉侯赛化学有限公司(HCCL)150kt/a粒状普钙(GSSP)工程是由南化集团设计院和中国化工建设总公司共同承包的化肥交钥匙工程.该工程包括60kt/a硫磺制酸及150kt/a粒状普钙,硫酸工艺采用快速熔硫、自然沉降和3+1”两转两吸工艺,普钙采用湿磨磷矿、磷矿浆混化、皮带化沉、造粒和干燥工艺.中方主要负责工程的设计,主要设备、材料的采购,设备安装和开车指导;外方负责工程的土建设计,施工及设备、材料的安装工作.工程造价约406万美元(不含外方负责工作费用).目前,已完成工程的详细设计和主要设备的采购,预计工程将于2002年8月完工投产,工程建成后,可极大缓解该国的化肥紧缺状况.(南化集团设计院邱世庭)  相似文献   
55.
CPP薄膜中成核剂用量对其性能的影响   总被引:1,自引:0,他引:1  
研究成核剂A3用量对CPP薄膜光学性能、机械性能、热封性能和摩擦系数的影响,结果表明,添加0.6%-1.2%质量比A3成核剂,能使雾度在4%以下,对透明性基本无影响,能同时提高拉伸强度和断裂伸长率,热封强度提高10%左右,起始热封温度保持127℃,热粘强度无变化,摩擦系数先升后降,动摩擦系数比静摩擦系数下降更快。  相似文献   
56.
信息与动态     
甲醇合成催化剂保护剂实现国产化  甲醇合成催化剂保护剂能有效地脱除原料气中羰基铁、镍 ,延长甲醇合成催化剂寿命 ,降低粗甲醇中的杂质含量 ,具有精脱硫和脱除羰基铁、镍的双重功能。由齐鲁石化公司研究院研制开发的QXJ- 0 1和QMG - 0 1甲醇合成催化剂保护剂分别于 2 0 0 0年和 2 0 0 1年在齐鲁石化第二化肥厂1 0万t/a甲醇上实现国产化 ,综合性能分别达到德国南方化学公司的K30 6和丹麦托普索公司的MG90 1水平。(王冬梅 周广林 )轴径向变换反应器实现国产化  轴径向变换反应器由瑞士卡萨尔公司首先实现工业化 ,在中国已有…  相似文献   
57.
山东海化魁星化工有限公司研制开发的三聚氰胺可拆卸式活动外罩燃煤熔盐炉最近通过鉴定,并获得国家专利。 该炉是在原三联双程燃煤熔盐炉基础上自行研制开发的国内首创的可拆卸式活动外罩熔盐炉,有效地解决了该公司6000 t/a三聚氰胺装置先天性供热不足的难题,使装置日产量提高了3 t多,并逐渐实现了稳产增产,年增经济效益161万元。该炉以煤为原料,以无机高温载体熔盐为载热介质,对工艺进行加热,广泛应用于化工、冶金等行业,可在300~1000℃范围内的多种工业领域使用,具有升温快、供热量大、运转平稳、高效节能、维修方便等特点。其外罩和每组膜管螺旋面均可迅速拆开、吊出,有效地解决了炉内维修所带来的困难和不便,并且使热效率和容量得到很大提高,为我国三聚氰胺行业熔盐炉的改造开辟了一条新路。  相似文献   
58.
Microbial fuel cells (MFCs) are bio-electrochemical systems that can directly convert the chemical energy contained in an effluent into bioelectricity by the action of microorganisms. The performance of these devices is heavily impacted by the choice of the material that forms the cathode. This work focuses on the assessment of ferroelectric and photocatalytic materials as a new class of non-precious catalysts for MFC cathode construction. A series of cathodes based on mixed oxide solid solution of LiTaO3 with WO3 formulated as Li1-xTa1-xWxO3 (x=0, 0.10, 0.20 and 0.25), were prepared and investigated in MFCs. The catalyst phases were synthesized, identified and characterized by DRX, PSD, MET and UV-Vis absorption spectroscopy. The cathodes were tested as photoelectrocatalysts in the presence and in the absence of visible light in devices fed with industrial wastewater. The results revealed that the catalytic activity of the cathodes strongly depends on the ratio of substitution of W6+ in the LiTaO3 matrix. The maximum power densities generated by the MFC working with this series of cathodes increased from 60.45 mW·m-3 for x=0.00 (LiTaO3) to 107.2 mW·m-3 for x=0.10, showing that insertion of W6+ in the tantalate matrix can improve the photocatalytic activity of this material. Moreover, MFCs operating under optimal conditions were capable of reducing the load of chemical oxygen demand by 79% (CODinitial=1030 mg·L-1).  相似文献   
59.
We have tested the insect antifeedant and toxic activity of 43 norditerpenoid alkaloids on Spodoptera littoralis and Leptinotarsa decemlineata including eserine (physostigmine), anabasine, and atropine. Antifeedant effects of the test compounds were structure- and species-dependent. The most active antifeedants to L. decemlineata were 1,14-diacetylcardiopetaline (9) and 18-hydroxy- 14-O-methylgadesine (33), followed by 8-O-methylconsolarine (12), 14-O-acetyldelectinine (27), karakoline (7), cardiopetaline (8), 18-O-demethylpubescenine (13), 14-O-acetyldeltatsine (18), takaosamine (21), ajadine (24), and 8-O-methylcolumbianine (6) (EC50 < 1 microg/cm2). This insect showed a moderate response to atropine. S. littoralis had the strongest antifeedant response to 24, 18, 14-O-acetyldelcosine (19), and delphatine (29) (EC50 < 3 microg/cm2). None of the model substances affected the feeding behavior of this insect. The most toxic compound to L. decemlineata was aconitine (1), followed by cardiopetalidine (10) (% mortality > 60), 14-deacetylpubescenine (14), 18-O-benzoyl-18-O-demethyl-14-O-deacetylpubescenine (17), 14-O-acetyldelcosine (19), 14-deacetylajadine (25) and methyllycaconitine (30) (% mortality > 45). Orally injected S. littoralis larvae were negatively affected by 1, cardiopetaline (8), 10, 1,14-O-acetylcardiopetalidina (11), 12, 14, 1,18-O-diacetyl-19-oxo-gigactonine (41), olivimine (43), and eserine in varying degrees. Their antifeedant or insecticidal potencies did not parallel their reported nAChR binding activity, but did correlate with the agonist/antagonist insecticidal/antifeedant model proposed for nicotininc insecticides. A few compounds [14, tuguaconitine (38), 14-demethyldelboxine (40), 19, dehydrodelsoline (36), 18-O-demethylpubescenine (13), 41, 9, and delcosine (23)] had selective cytotoxic effects to ward insect-derived Sf9 cells. None were cytotoxic to mammalian CHO cells and none increased Trypanosoma cruzi mortality. The selective cytotoxic effects of some structures indicate that they can act on biological targets other than neuroreceptors.  相似文献   
60.
Advanced nanoarchitectures for solar photocatalytic applications   总被引:5,自引:0,他引:5  
  相似文献   
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