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1.
以EGME(乙二醇乙醚)为溶剂, AIBN(偶氮二异丁腈)为引发剂合成 GMA/HEMA/NVP(α-甲基丙烯酸缩水甘油酯/α-甲基丙烯酸-β-羟基 乙酯/N-乙烯基-α-吡咯烷酮)三元共聚物。将它涂覆在聚酯PC片上 进行升温固化,测试涂层的防雾性能和硬度。并研究了SR205(三缩三乙 二醇二甲基丙烯酸酯)涂料对涂膜防雾性能和硬度的影响.  相似文献   

2.
制备了PVA(聚乙烯醇)/CMC(羧甲基纤维素)渗透汽化复合膜。研究了PVA/CMC用量比、交联剂用量、乙醇浓度、渗透汽化时间等因素对膜的渗透汽化性能的影响。发现PVA/CMC复合膜对85-98.3wt%乙醇溶液表现为水优先透过。在26.5°C和1atm下,90.8wt%乙醇溶液渗透汽化3小时、膜内乙醇浓度增至98.3wt%。达到了较好的醇/水分离效果  相似文献   

3.
苹果褪绿叶斑病毒(ACLSV)是感染仁果类和核果类果树的重要病毒.作者应用RT-PCR技术和PAS-ELISA技术成功地检测了该病毒,并对指示植物中感染该病毒的检测结果进行了报道.试验结果表明,RT-PCR技术的检测灵敏度是PAS-ELISA技术的8000倍.  相似文献   

4.
1.驻美国大使馆:地址:THEEMBASSYOFTHEPEOPLE’SRE-PUBIJCOFCHINA,2300CONNECTICUTAVENUE,N.W.WASHINGTON,DC20008电话:(202)3282500(202)7456500传真...  相似文献   

5.
MICROSTRUCTUREANDMECHANISMOFANEWTYPEOFNi-Fe-W-P-SWEAR-RESISTANTBRUSHPLATINGLAYERHuiWenhua(惠文华)ZhangJinping(张瑾平)ShaoLiwei(邵力为)...  相似文献   

6.
AMODIFIEDCRANK-NICOLSONSCHEMEFORTHEINITIAL-BOUNDARYVALUEPROBLEMOFSUPERTHERMALELECTRONTRANSPORTEQUATIONSunZhizhong(孙志忠)(Depart...  相似文献   

7.
PERFORMANCESIMULATIONANDANALYSISOFAQUAAMMONIAABSORPTION-RESORPTIONHEATPUMPDuKai(杜垲)YangSiwen(杨思文)ZhangSiqun(张思群)(Departmentof...  相似文献   

8.
目的观察rhEPO和睾酮对低氧小鼠血清ASTase、ALTase、LDHase活性的影响.方法应用低压舱小鼠实验(0.42atm,22h/d, 6days),分别注射rhEPO(200u/kg·d)、宰酮(2.5 mg/d)、皮质醇(0.5 mg/d),检测血清酶活性、血清 EPO浓度和 Hct.结果rhEPO和睾酮不同程度地抑制低氧小鼠血清酶活性.结论rhEPO和睾酮对低氧动物肝功能具有不同程度地保护效应。  相似文献   

9.
AMINI-CAPACITANCEPROBEFORMEASURINGTHELOCALVOIDFRACTIONINGAS-SOLIDFLUIDIZEDBEDSGuiKeting(归柯庭)HanJitian(韩吉田)ShiMingheng(施明恒)(De...  相似文献   

10.
第一试一、选择题1.在△ABC中,若ctgAtgA2+ctgBtgB2+ctgCtgC2≥1,则△ABC的形状是(  ).A.任意三角形  B.直角三角形C.钝角三角形  D.等边三角形2.已知x,y∈R,且3x+5y≥3-y+5-x,则x与y满足(  ).A.x+y>0  B.x+y≥0C.x+y<0  D.x+y≤03.已知P是正方形ABCD所在空间任一点,则PA2-PD2与PB2-PC2的大小关系是(  ).A.PA2-PD2>PB2-PC2B.PA2-PD2<PB2-PC2C.PA2-P…  相似文献   

11.
研究了橡塑比、过氧化物复合硫化体系及KH-570硅烷偶联剂对动态硫化EPDM/PP/SiO2共混物的力学性能的影响.结果表明,随着PP含量的增加.动态硫化EPDM/PP/SiO2共混物的力学性能和硬度增加,但压缩永久变形增加,断裂伸长率却减小.过氧化物复合硫化体系中,当DCP为1.5份时,动态硫化EPDM/PP/SiO2共混物的综合物理力学性能较好.加入KH-570改性的白炭黑,对EPDM/PP/SiO2共混物起到补强的作用;且提高共混物的交联密度,降低压缩永久变形.  相似文献   

12.
以硅酸钠为硅源原位生成SiO2增强橡胶   总被引:1,自引:0,他引:1  
采用溶胶-凝胶技术,以硅酸钠为原料制得活性硅醇的THF溶液,再与天然橡胶及少量偶联剂混合,原位生成二氧化硅(SiO2)增强橡胶。论述了在酸性条件下制备特性聚硅酸的最佳反应条件,对温度,pH值及硅酸钠浓度的影响进行了研究。同时用热重分析(TG)测试材料的热性能,电子拉力机测量SiO2含量对材料的力学性能的影响。为弹性体杂化材料的制备提供了一种更具实用价值的新方法。  相似文献   

13.
以尼龙6(PA6)、全硫化丁腈橡胶(UFNBRP)、马来酸酐(MAH)和过氧化物为主要原料,采用一步增容法制备尼龙6/全硫化丁腈橡胶复合材料,研究MAH含量对复合材料性能的影响。复合材料的形态分析表明,一步增容能降低和均化分散相UFNBRP的粒径,当MAH含量为1.0份时,分散相的粒径最小,粒径分布最窄。从力学性能分析可以看出,加入1.0份MAH时,复合材料的缺口冲击强度最大,与纯PA6相比提高了158 %,而拉伸性能仅少量下降。动态机械性能进一步证实一步增容法能有效改善PA6和UFNBRP两相的界面结合。  相似文献   

14.
采用浸渍法在二氧化硅多孔材料中负载壳聚糖制备壳聚糖/SiO2复合材料,通过X射线衍射、扫描电子显微镜、傅立叶变换红外光谱等方法对所制备材料的组成与结构进行了表征,采用热重-差示扫描量热法研究了复合材料的热稳定性,采用电流中断法测定所制备材料的电导率来衡量其质子传导性能,并考察了壳聚糖溶液浓度对壳聚糖/SiO2复合材料导电性能的影响。结果表明,壳聚糖/SiO2复合材料具有较高的热稳定性,复合材料的电导率随着壳聚糖乙酸溶液浓度的增加而增加,当壳聚糖乙酸溶液质量百分比浓度为2.5%时,电导率可达1.82 S/cm。  相似文献   

15.
Phenolic formaldehyde(PF)and epoxy(EP)resins are commonly used in electronic packaging. In this paper, high-ohmic resistors(2.2 M?, ±0.5%,)with Cr-Si film were coated by PF/EP paint, and the resulting coated resistors were used for heat and humid(HH)experiments. The experimental results show that the corrosion of bandlike resistive films is selective and isotropic, and that the corrosion spots in resistive films all form along grooves and extend in the same direction. It is revealed that OH~- ions are generated due to the electrochemical reactions of resistive film in HH experiments, so a NaOH aqueous solution with pH about 10 was used to study the effects of absorbed water and OH~- ions on PF/EP polymer film. The results indicates that the color of some part on PF/EP polymer film changes due to corrosion, and that the corrosion part of the polymer film is easy to be peeled off. It can be inferred that OH~- ions generated in HH experiments may play a catalytic role in the chemical reactions between polymer film and the absorbed water, which accelerates the degradation of PF/EP protection film for a resistor.  相似文献   

16.
采用电沉积的方式将纳米金固载在玻碳电极表面,制得纳米金修饰玻碳电极(NG/GCE)。研究了去甲肾上腺素(NE)在NG/GCE的电化学行为,发现NG/GCE不仅对NE有良好的催化和富集作用,而且能将NE和抗坏血酸(AA)的循环伏安氧化峰很好地区分开,可在抗坏血酸共存下选择性测定NE。  相似文献   

17.
Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.  相似文献   

18.
INTRODUCTION Mg-based alloys are considered as potentialcandidates for hydrogen storage materials because oftheir large hydrogen capacity (Reilly and Wiswall,1968; Pedersen and Larsen, 1993). However, asMg-based alloys desorb hydrogen at temperatureshigher than 600 K, they are not applicable to practicaluse. Many researches have studied to improve hy-driding/dehydriding kinetics and to lower the workingtemperature (Wang et al., 2002; Tsushio et al., 1998;Spassov and K?ster, 1998; Orim…  相似文献   

19.
20.
探索性实践:外语课堂研究新途径   总被引:1,自引:0,他引:1  
探索性实践是一种以实践者为主体的教育研究途径。通过梳理探索性实践的提出、涵义、其原则的演变和发展,分析探索性实践与行动研究的区别,发现探索性实践为外语课堂研究提供了崭新的视角,是实现教师专业化发展、提升教师职业生涯品质的有效途径。  相似文献   

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