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《化工标准.计量.质量》2009,(8):34-36
欧盟:修订欧洲议会和理事会指令98/8/EC,将杀鼠迷作为一种活性物质包括在其附件I中
通报号:G/TBT/N/EEC/257
通报日期:2009年3月18日 相似文献
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《化工标准.计量.质量》2009,(5):48-48
欧盟是我国的第一大贸易伙伴。欧盟CE标志作为出口欧盟的重要通行证,历来被视为制造商打开并进入欧洲市场的“护照”,也是欧盟阻止不合格产品进口的一道最重要、最基础的安全防线。按现行规定,在欧盟市场销售的工业产品,必须贴有CE标志,否则不得上市销售。玩具指令(88/378/EEC)、机械指令(98/37/EEC)、低电压指令(73/23/EEC,2006/95/EC)等众多欧盟的重要指令均对CE标志作了要求。 相似文献
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通过拉伸实验和老化实验,研究了玄武岩纤维含量对BF/PLA拉伸性能、抗冲击性能及耐老化性能的影响规律,通过DSC实验得到BF/PLA复合材料的结晶度,分析其耐老化原因。随着质量分数增加,其拉伸强度增加可达到141 MPa,弹性模量达到5 GPa,达到峰值后又减小。质量分数达到30%时,缺口冲击强度和非缺口冲击强度分别达到6.7 kJ/m2和20.76 kJ/m2。DSC实验结果表明,随着玄武岩纤维含量的增加,聚乳酸复合材料的结晶度由34.6%增加到54.6%,而结晶度的增加可以减缓聚乳酸的降解速度。当质量分数达到60%时,老化实验后的弹性模量可以保持降解前的77%,延缓降解速度较为明显。经分析,拉伸强度与玄武岩纤维质量分数呈二次多项式关系,而弹性模量与玄武岩纤维质量分数之间呈线性关系。这种函数关系不受材料力学性能下降的影响。 相似文献
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为制备结构均匀的多孔SiC陶瓷的料浆,本文比较了不同质量分数(40%~60%)的SiC浆料的剪切应力和黏度随剪切速率的变化.结果表明:浆料的等电点在3.6左右,Zeta电位值随着pH值的增加而减小,碱性环境下分散效果更好;用Casson方程拟合浆料的剪切应力,相关系数在0.98以上,随着固相含量的增加,拟合的极限粘度和屈服应力增加;当剪切速率达到100 s-1时,固相含量为40%~55%浆料的粘度都在1 Pa·s以下,固相含量为60% 的浆料粘度大概是2.1 Pa·s. 相似文献
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Zhenxing Shen Junji Cao Richard Arimoto Yuemei Han Chongshu Zhu Jing Tian 《Aerosol science and technology》2013,47(6):461-472
Daily mass concentrations of water-soluble inorganic (WS-i) ions, organic carbon (OC), and elemental carbon (EC) were determined for fine particulate matter (PM1, particles < 1.0 μm in diameter) collected at Xi'an, China. The annual mean PM1 mass concentration was 127.3 ± 62.1 μg m–3: WS-i ions accounted for ~38% of the PM1 mass; carbonaceous aerosol was ~30%; and an unidentified fraction, probably mostly mineral dust, was ~32%. WS-i ions and carbonaceous aerosol were the dominant species in winter and autumn, whereas the unidentified fraction had stronger influences in spring and summer. Ion balance calculations indicate that PM1 was more acidic than PM2.5 from the same site. PM1 mass, sulfate and nitrate concentrations followed the order winter > spring > autumn > summer, but OC and EC levels were higher in autumn than spring. Annual mean OC and EC concentrations were 21.0 ± 12.0 μg m?3 and 5.1 ± 2.7 μg m–3 with high OC/EC ratios, presumably reflecting emissions from coal combustion and biomass burning. Secondary organic carbon, estimated from the minimum OC/EC ratios, comprised 28.9% of the OC. Positive matrix factorization (PMF) analysis indicates that secondary aerosol and combustion emissions were the major sources for PM1. 相似文献
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分别采用环境友好型的磷氮系列新型阻燃剂和聚偏氟乙烯(PVDF)对聚酯(PET)进行改性,通过皮芯复合纺丝制备阻燃防水多功能PET纤维,对纤维的制备工艺及其阻燃性能和防水性能进行了研究。结果表明:添加环氧树脂包覆磷酸铵(CK-APP105)质量分数为6%时,纤维极限氧指数值高达30.7%,具有良好的阻燃效果;CK-APP105/三聚氰胺脲酸盐(CK-MCA)质量比为7/3时,协同阻燃效果最佳;芯层料添加质量分数5.6%的CK-APP105和2.4%的CK-MCA,皮层料添加质量分数6%的PVDF,所制得纤维的断裂强度为3.25 cN/dtex,断裂伸长率为67.32%,极限氧指数为30.9%,与水的接触角大于90°;改性PET纤维具有较好的阻燃性能和防水性能。 相似文献
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Joseph W. Nicholas Carolyn A. Koh E. Dendy Sloan 《American Institute of Chemical Engineers》2009,55(7):1889-1897
Gas hydrate/ice deposition from a dissolved water phase in a liquid condensate system was modeled using a mass and energy balance. The same modeling parameters were used to model three flow loop experiments (1.89 and 2.83 L/min flow rate deposition tests and a 1.89 L/min dissociation test) with acceptable accuracy. Relative changes in both temperature and pressure drop were modeled using an ice deposit with a 67% void fraction. © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
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用相容性较好的乙烯基类单体溶解回收废聚苯乙烯泡沫材料(EPS),并通过乳液聚合方法制备出一种稳定的低成本无溶剂型纸张表面施胶剂,将其与糊化好的氧化淀粉复配可制取质量分数为4%的施胶液。结果表明:制备施胶剂的最佳工艺条件为m(十二烷基硫酸钠)∶m(OP-10)=2∶1,w(引发剂)=0.5%~0.6%,反应时间为80min,w(废EPS)=5%~10%(相对于复合单体而言);采用质量分数为4%的施胶液对纸张表面进行施胶,可使纸张的施胶度、挺度和环压强度分别提高17倍、33%和21%。 相似文献
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Historically, obtaining quantitative chemical information using laser desorption ionization mass spectrometry for analyzing individual aerosol particles has been quite challenging. This is due in large part to fluctuations in the absolute ion signals resulting from inhomogeneities in the laser beam profile, as well as chemical matrix effects. Progress has been made in quantifying atomic species using high laser powers, but very few studies have been performed quantifying molecular species. In this study, promising results are obtained using a new approach to measure the fraction of organic carbon (OC) associated with elemental carbon (EC) in aerosol particles using single particle laser desorption ionization. A tandem differential mobility analyzer (TDMA) is used to generate OC/EC particles by size selecting EC particles of a given mobility diameter and then coating them with known thicknesses of OC measured using a second DMA. The mass spectra of the OC/EC particles exiting the second DMA are measured using an ultrafine aerosol time-of-flight mass spectrometer (UF-ATOFMS). A calibration curve is produced with a linear correlation (R2 = 0.98) over the range of OC/EC ion intensity ratios observed in source and ambient studies. Importantly, the OC/EC values measured in ambient field tests with the UF-ATOFMS show a linear correlation (R2 = 0.69) with OC/EC mass ratios obtained using semi-continuous filter based thermo-optical measurements. The calibration procedure established herein represents a significant step toward quantification of OC and EC in sub-micron ambient particles using laser desorption ionization mass spectrometry. 相似文献
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Hβ沸石修饰的复合氧化物对苯酚羟基化反应的催化作用 总被引:1,自引:0,他引:1
采用不同硅铝比的Hβ沸石对铁基复合金属氧化物催化剂进行了修饰,发现复合氧化物催化体系中掺入适量具有特定结构的Hβ沸石,可以提高催化剂的活性,缩短甚至消除羟基化反应诱导期,避免由于未反应过氧化氢的积累增加反应器运行的风险,提高过氧化氢有效利用率和目标产物选择性。但过多的Hβ沸石导致苯酚和苯二酚缩合生成不溶于水的焦油,降低了羟基化反应的目标产物选择性。比较合适的修饰用Hβ沸石包括Hβ-80、Hβ-63和Hβ-48。比较好的Hβ-80沸石掺入质量分数为7%,以7% Hβ沸石修饰的Fe-Cu-Sn-Zn-O/γ-Al2O3复合氧化物作催化剂,反应温度65 ℃、反应时间30 min、苯酚5.3 g、溶剂水10.0 g、m(苯酚)∶m(催化剂)=294、n(过氧化氢)∶n(苯酚)=0.33时,反应诱导期不到1 min,苯酚转化率22.3%,苯二酚选择性91.9%,过氧化氢有效利用率62.1%。 相似文献
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制备了MgO/γ-Al2O3固体碱催化剂,采用X射线衍射、CO2-TPD程序升温脱附等手段表征了催化剂的结构和碱性质。结果表明:MgO负载量(质量分数)对催化剂上MgO的分散程度和催化剂碱性质有着重要影响。负载MgO后,γ-Al2O3仍然保持了原有的结构。当MgO的负载量小于9%时,几乎检测不到MgO特征衍射峰。催化剂的碱量随MgO负载量的增加而逐步提高,当负载量为9%时其碱量达到最大。考察了MgO负载量、反应时间、反应温度对碳酸乙烯酯(EC)水解反应合成乙二醇(EG)的影响。随着MgO负载量的增加,EC转化率逐渐上升。工艺条件研究表明:140℃和3 h以及酯水比(摩尔比)1∶1为最佳催化反应条件。采用9%MgO/γ-Al2O3为催化剂,在最佳工艺条件下,EG收率高达95.6%。 相似文献