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661.
662.
火焰原子吸收光谱法测定土壤中镉 总被引:5,自引:0,他引:5
吕跃明 《理化检验(化学分册)》2004,40(8):468-469
用HCl-HNO3-HF-HCIO4消解土样,加入四氯化碳萃取消解液中的Cd-DDTC的配合物,用HNO3-H2O2混合液反萃取。用火焰原子吸收光谱法测定反萃取的水相中镉。 相似文献
663.
流动注射离子交换预浓集火焰原子吸收光谱法直接测定人尿中痕量镉 总被引:2,自引:0,他引:2
应用高效的流动注射在线离子交换预浓集火焰原子吸收光谱测定系统直接测定了人尿中痕量镉。选择200μL锥形离子交换柱,内装多孔玻璃固定化的8-羟基喹啉离子交换剂,在pH9条件下样品流速为3.5mL/min,40s装样,用2mol/LHCl洗脱,在分析速度为60样/h,获得30倍的富集倍率。检出限为0.3μg/L。镉含量水平为40μg/L的尿样,连续测定11次的相对标准偏差为1.5%。尿标准参考物...? 相似文献
664.
非过滤法共沉淀富集—火焰原子吸收测定饮水中镉铜铅 总被引:3,自引:0,他引:3
在中性或弱碱性条件下,向被没水样中加入适量Bi^3+和硫化钠,使水样中Cd^2+,Cu^2+,Pb^2+与Bi^3+一起硫化物(CdS,CuS,PbS)和Bi2S3的共沉淀,加入明矾加速硫化物的沉淀,凝结,然后用虹吸法吸去上层清液(无须过滤),将沉淀物用热稀硝酸溶液,以火焰原子吸收法测定这三个元素的含量。方法简便,实用,且具有较高的准确率和精密度,尤其适于对大体积水样的沉淀富集。 相似文献
665.
对血清中锂的火焰原子吸收分光光度分析法(FAAS)进行了研究,发现血清在0.24mol/LHNO3介质中,用3000×10-6Al3+作为碱土金属干扰的抑制剂,用FAAS法测定血清理,其回收率和精密度都很好,分别为104.7%和2.8%.本法1%吸收的灵敏度为0.033μg/mL。采用本法对服用碳酸锂治疗苯中毒的患者血清中锂进行了测定,其含量在0.75~4.64μg/mL之间,结果令人满意。 相似文献
666.
赖心 《理化检验(化学分册)》2003,39(9):523-524,526
研究了用火焰原子吸收光谱法间接测定饲料预混硒中硒,与其它方法比较,简单、快速,测定的相对标准偏差小于5.0%,回收率为96.3%-104.0%,检出限为0.0005%。 相似文献
667.
火焰原子吸收光谱法测定人发中微量元素前处理方法研究 总被引:3,自引:0,他引:3
王晓梅 《理化检验(化学分册)》2002,38(6):297-298
对火焰原子吸收光谱法测定人发中量元素的前处理方法进行了研究,发现用HNO3:HC1O4=8:1进行消化,三蒸水直接稀释定容,结果满意.用干法灰化,温度不宜高于600℃. 相似文献
668.
Roman culture employed architectural terracotta made from baked clay as original material to manufacture ceramic pieces. It was often used as a basis for construction of functional and/or decorative elements in roofs, such as plane and curve tiles as well as antefixes with their corresponding “imbrexes”. Some of them are conserved nowadays. They were collected in Roman quarries discovered in old cities and villages sited in the Hispania Citerior (northeast of Spain in Roman age). A study of the origin and manufacturing process (moulding, baking, touching up and painting) of these terracotta pieces has been made on the basis of the data obtained from a physicochemical characterization of samples. The used techniques were mainly flame absorption and emission spectrometry for the elemental analysis (major and minor elements), dilatometry for the study of thermal behaviour, scanning electron microscopy (SEM) for observation of thin layers and X-ray diffraction spectrometry (XRD) for mineralogical composition. In addition, a supervised pattern recognition programme was applied to the results for a selected group of 85 samples and five variables (chromium, copper, lead, nickel and zinc contents). Dilatometry and SEM results showed baking temperatures of these materials below 900 °C and the existence of zones with very different porosity in the same ceramic piece. Results obtained from multielemental analysis and multivariate statistical study by linear discriminant analysis lead us to the following conclusions: (i) the high content of lead found in a large number of antefixes demonstrates the use of lead oxide as an additive in the lime grout treatment, (ii) different contents of Cu, Zn, Cr, and Ni were indicative of the use of varied clay types in the manufacture process (even in the same production centre) as well as of the existence of a pigmentation process, although this last affirmation is not corroborated by the presence of remains of evident painting in the ceramic pieces, (iii) samples can be classified according to the places where these pieces came from and (iv) more variety in their composition was found in Roman age terracotta production centres. 相似文献
669.
乳化法-火焰原子吸收光谱法测定奶茶粉中铁 总被引:5,自引:0,他引:5
采用乳化法将奶茶粉样品用乳化剂OP乳化成分散均匀且稳定的乳浊液,直接喷入空气 乙炔火焰中,以标准加入法测定铁含量。测定结果与灰化法一致,检出限(3σ)为0.028μg·ml-1,RSD小于2.5%,该方法简便、快速、准确。 相似文献
670.
A calibration model has been developed in order to overcome matrix effects in atomic absorption measurements. The model uses two independent variables for analyte quantification (the amount of the sample and the amount of analyte added). The dependent variable is the absorbance measured. The method also allows matrix interferences to be controlled without prior knowledge of matrix composition. The method is applied to iron determination by FAAS in the presence of large amounts of copper. Direct calibration and standard addition are also performed in order to compare them with the new empirical model. Results show that the error in iron determination could be –42% when direct calibration is applied and +10% when the standard addition method is used, whereas the proposed model decreases the error to –20%. 相似文献