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1.
Strains from the cellulose-containing environment were collected. Primary screening(by filter-paper Hutchison solid culture medium and sodium carboxymethylcellulose solid culture medium) and reelection(by filter-paper inorganic salt culture medium and sodium carboxymethylcellulosc Congo red coltnre medium) indicated that five strains obtained were best suited for high performance cellulose degradation. Determination of sodium carboxymethylcellulose activity(CMCA) and filter paper activity(FPA) was accomplished for each of the five. The strongest of the five in CMCA and FPA was applied to the production of cellulose bioethanol by separate hydrolysis and fermentation(SHF) and simultaneous saccharification and fermentation(SSF) respectively.  相似文献   
2.
Introduction The length of cellulose, one of the most impor-tant properties of raw material in the paper product,affects the tensile strength, tearability and breakingstrength of the paper product. The tensile strength in-creases with cellulose length, an…  相似文献   
3.
在AC、SMA、OGFC 3种级配形式的沥青混合料中分别掺加国产聚酯纤维、聚丙烯腈纤维和木质素纤维,测定纤维沥青混合料的路用性能,包括混合料马歇尔稳定度、高温稳定性、低温抗裂性、水稳性、渗水性和抗滑性能,分析了纤维增强沥青混合料强度形成机理.与无纤维沥青混合料试验结果进行对比,3种纤维沥青混合料的路用性能都有不同程度的提高,聚酯纤维与聚丙烯腈纤维的综合改善性能优于木质素纤维.通过车辙试验,确定了聚酯纤维满足不同交通量下的设计用量.技术经济分析表明,纤维沥青混合料经济效益明显,具有良好的应用前景.  相似文献   
4.
以阔叶材纸浆板为原料,研究硫酸水解条件下纤维素微晶悬浮液制备的实验条件,以及纤维素胆甾型液晶织态结构的形成、影响因素及其机理.设计两组实验,通过光学显微镜研究了温度变化对水解后纤维素微晶粒径分布的影响;通过FTIR表征水解前后纤维素微晶表面官能团的变化;通过偏光显微镜确定纤维素胆甾型液晶织构形成的临界浓度.结果表明:在...  相似文献   
5.
利用有限元软件ABAQUS对上覆硬壳层双层地基室内模型试验进行数值模拟.通过分析等效塑性应变分布云图与位移矢量分布图,确定了双层地基的破坏形式为冲剪破坏;硬壳层厚度的增加减缓了下卧软土层变形区的开展,但是地基承载能力增加不明显;加入纤维素的固化剂提高了硬壳层的强度,增加了地基的承载能力.在地基破坏特征和极限承载力方面,数值模拟与模型试验所得结果的吻合程度较高.  相似文献   
6.
在柠檬酸介质中:V5+强烈地催化KBrO3氧化甲基红的反应,据此建立了催化动力学光度法测定痕量V5+的新方法。本方法的检出限为0.12ng/ml,测定范围为0~6.4ng/ml,并用本法对地下水进行了分析。  相似文献   
7.
纤维对混凝土抗渗性能及硬化水泥浆体孔结构的影响   总被引:1,自引:0,他引:1  
研究了纤维掺量0.9 kg/m3时,纤维素纤维UF500、聚丙烯纤维对混凝土抗渗性能的影响。试验结果表明:这两种纤维均可以明显改善混凝土的抗渗性,改善程度均在80%以上;且纤维素纤维UF500的改善效果较聚丙烯纤维高出16%。结合压汞法对纤维掺量0~0.3%(质量百分比)的各28 d硬化水泥浆体的孔结构进行了测试与分析,探讨纤维对硬化水泥浆体孔结构的影响。结果表明:相同纤维掺量下,UF500纤维对水泥浆体孔隙率、平均孔径以及孔径分布的改善效果都明显高于聚丙烯纤维;综合孔结构参数测试结果,试验掺量范围内纤维素纤维UF500的最佳掺量为0.23%,聚丙烯纤维以0.15%最佳。  相似文献   
8.
对预拌砌筑砂浆综合性能进行研究,并且针对预拌砌筑砂浆中矿粉、粉煤灰和纤维素的不同掺量对砂浆各项性能产生的影响进行分析,从而得出3种掺加材料各自较为合理的掺配比例。  相似文献   
9.
肝癌特异γ-谷氨酰转肽酶同功酶Ⅱ活性检测及其临床价值   总被引:2,自引:0,他引:2  
目的 探讨患者血清肝癌特异γ 谷氨酰转肽酶同功酶Ⅱ (GGTⅡ )活性与肝癌生物学行为的相关性及其临床价值。方法 用硝酸纤维膜特异免疫吸附法 (NSIA)对患者血清中GGTⅡ进行定性检测。结果 原发性肝癌(PHC)检测敏感性为 83 .77% ,特异性为 98.0 4% ,转移性肝癌 (MLT)诊断阳性率为 7.5 5 % ,对AFP阴性的PHC患者检测阳性率为 65 .91%。结论 NSIA检测GGTⅡ简便、快速、微量、灵敏、经济 ,可用于PHC的辅助诊断、鉴别诊断和早期发现 ,也可作为其他肝癌标志物的补充  相似文献   
10.
The objective of the present study is the assessment of the environmental impact of a bivalent (bi-fuel) vehicle, running either on gasoline or compressed natural gas (CNG). To that aim, a Euro 6 passenger car was tested under various real-world driving conditions. In order to cover the full range of conventional powertrains currently in the market, the tests were also repeated on a Euro 6 diesel passenger car. Both cars were driven in two routes, the first complying with the regulation limits and the second going beyond them. Carbon monoxide (CO), nitrogen oxides (NOx) and particle number (PN) emissions were recorded using a Portable Emissions Measurement System (PEMS). Apart from the aggregated emission levels, in g/km, the exact emission location along the route was also assessed. Natural gas proved beneficial for CO and PN emissions, the level of which always remained below the respective legislation limits. On the other hand, under the dynamic driving conditions with gasoline, the relevant limits were exceeded. Cold start, occurring at the beginning of the urban part, and motorway driving were identified as major contributors to total emissions, especially in gasoline mode. However, the application of natural gas was associated with a penalty in NOx emissions, which were significantly increased as compared to gasoline. Local peaks within the urban part were identified in CNG mode. In any case, the diesel vehicle was by far the highest NOx emitter.  相似文献   
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