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111.
112.
采用GC-MS联用法,对车用汽油中含有的非常规添加物甲缩醛、碳酸二甲酯和N-甲基苯胺进行了定性筛查和定量检测。其中,定性分析采用全离子扫描、与标准物质保留时间对照及与标准物质的特征离子图对比等方法;定量分析采用特征定量离子提取结合内标法。同时考察了汽油本底对这3种化合物定性检测和定量测定的影响。实验结果表明,3种化合物的回收率在95.83%~101.11%之间,相对标准偏差小于5%,定量数据准确可靠;各组分含量在2%(w)以内,线性响应良好;甲缩醛和碳酸二甲酯的检测限为0.01%(w),N-甲基苯胺的检测限为0.1%(w)。该方法重复性和再现性均能满足常规分析要求。 相似文献
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Xu-Liang Cao Jiping Zhu Stephen MacDonald Kaela Lalonde Bob Dabeka Mamady Cisse 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(6):808-813
An isotope dilution method based on solvent extraction followed by GC–MS analysis was developed and used to determine aniline in vegetable and fruit samples collected from the Canadian total diet study. Aniline was not detected in any of the 23 vegetable samples from the 2005 total diet study at a method detection limit of 0.01 mg kg–1. Among the 16 fruit samples, it was detected only in apple samples, with an average concentration of 0.278 mg kg–1. Aniline was not detected in apple samples collected in the 2002, 2003, 2006 or 2007 total diet studies, but it was detected in the apple samples collected from the 2001 and 2004 studies, at concentrations of 0.085 and 0.468 mg kg–1, respectively. The average aniline concentration for the 2001, 2004 and 2005 apple samples was 0.277 mg kg–1. Good repeatability of the method was observed with replicate analysis of apple samples, with relative standard deviations (RSD) ranging 3.8–21% and an average of 11%. 相似文献
115.
A promising gram-negative bacterial strain for the biodegradation of aniline as the sole carbon, nitrogen and energy sources was successfully isolated and identified as Delftia sp. XYJ6. The optimal temperature and pH for both the growth of Delftia sp. XYJ6 and the biodegradation of aniline were 30°C and 7.0, respectively. Initial aniline of 2000 mg8226;L-1 could be completely removed by the strain at 22 h, which showed that Delftia sp. XYJ6 had a strong ability in the biodegradation of aniline. It indicated that aniline was firstly converted to catechol catalyzed by aniline dioxygenase as a first product, which was then further biodegraded to cis,cis-muconic acid catalyzed by the catechol 1,2-dioxygenase of Delftia sp. XYJ6 as a second product. Cis,cis-muconic acid could also be further biodegraded to other small compound again. The pathway for the biodegradation of aniline by Delftia sp. XYJ6 was not previously reported. 相似文献
116.
络合萃取法处理含苯胺工业废水 总被引:8,自引:1,他引:7
采用络合萃取法处理苯胺废水。在常温、油水相比为1:10的条件下,将体积分数为70%磷酸三丁酯-30%煤油组成的萃取剂三级络合萃取苯胺废水,苯胺脱除率可达99.84%,提出了处理苯胺工业废水的综合工艺流程。 相似文献
117.
苯胺在超临界水中氧化反应动力学的研究 总被引:26,自引:5,他引:21
对苯胺在超临界水中的氧化反应进行了研究。发现随温度升高和停留时间延长,苯胺去除率和COD去除率增大,并且只有在温度高于898.15K条件下,苯胺氧化的COD去除率才有可能达到90%以上。在873.15K~898.15K范围内,温度对苯胺氧化的COD去除率有较显著的影响。在673.15K~748.15K、25.0MPa、300%过氧量、2.351×10-4mol(L-1苯胺浓度条件下,苯胺反应级数为1.554,反应的活化能为2.96(104J(mol-1,频率因子为6.69×103。 相似文献
118.
为获得在低温(10℃)条件下能高效降解苯胺的细菌,选取某化工厂污水处理厂曝气池污泥,通过驯化、分离、纯化,筛选出5株在低温条件下能高效地降解苯胺的菌种A1、A4、A7、A9、A14,采用16S rDNA测序与传统生理生化实验方法相结合对其进行鉴定,并研究其生理学特征和降解特性.结果表明:菌株A1,A4,A7,A9,A14在培养84h时,苯胺降解率分别为87.5%,82.9%,100%,91.5%和82.8%,当培养时间至96h时,5株菌的苯胺降解率均达到100%.其最适生长温度是15℃,在5~35℃的温度范围内均可以生长.最适pH为7.0.经鉴定A4、A9属于Delftia.sp,A7属于Acinetobacter.sp,A1、A14属于Pseudomonas.sp.保藏并深入研究这些低温苯胺高效降解微生物,可为苯胺类废水的工业化处理提供微生物资源,并且为提高污水净化效能奠定一定的理论基础. 相似文献
119.
An aqueous solution of aniline was oxidized in supercritical water with a flow reactor under the conditions of 25 MPa, 300% excess oxygen, 2.351×10-4 mol*L-1 aniline .GC-MS analysis of the oxidation products extracted from the aqueous reactor effluent permitted identification of compounds such as azobenzene, phenazine and acetic acid. The products could be classified as dimers,single-ring or ring-opening produces,carboxylic acids and ultimate products.The contents of dimers (such as azobenzene and phenazine) were greater than other products.A reaction network consistent with the experimental observations was developed. The study revealed that aniline might be oxidized to ultimate products through two parallel pathways. The formation of dimers such as azobenzene, phenazine and the further oxidation of these dimers were the main pathways. It was indicated experimentally that the rate controlling step of aniline oxidation was the further oxidation of azobenzene and phenazine, but not the further oxidation of organic acid such as acetic acid, formic acid and so on. 相似文献
120.