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91.
92.
Marie-Louise Scippo Soledad Rybertt Gauthier Eppe Anne-Cécile Massart Edwin De Pauw Guy Maghuin-Rogister 《Accreditation and quality assurance》2006,11(1-2):38-43
In the determination of contaminants (dioxins, polychlorinated biphenyls, polyaromatic hydrocarbons), cell-based assays are
useful methods for screening purposes: they are mainly characterized by high sample throughput and lower costs than the Mass
Spectrometry (MS)-based methods.
Although cell-based assays can be sensitive enough for the determination of dioxins and related substances in agreement with
the presently tolerable limits in food and feed (Regulation No. 2375/2001/EC and Directive 2003/57/EC respectively), their
lack of specificity make their use rather questionable in control laboratories.
In this paper, we present and compare results obtained from the analysis of a limited number of feed samples by both gas chromatography-high
resolution mass spectrometry (GC-HRMS) and cell-based assay (DR-CALUX: dioxin responsive-chemically activated luciferase gene
expression) methods. The DR-CALUX screening led to less than 10% false non-compliant and no false compliant results. In addition,
there is a good correlation between GC-HRMS and DR-CALUX data. However, these preliminary results have to be confirmed on
a larger number of samples to demonstrate that total toxic equivalent (TEQ), including dioxins, furans and dioxin-like polychlorobiphenyls
(PCBs) can be monitored in feed and food with a cell-based assay.
Presented at AOAC Europe/Eurachem Symposium March 2005, Brussels, Belgium 相似文献
93.
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95.
Wendell Costa Bila Reysla Maria da Silveira Mariano Valmin Ramos Silva Maria Emília Soares Martins dos Santos Joel Alves Lamounier Eduardo Ferriolli 《Isotopes in environmental and health studies》2017,53(4):327-343
The main aim goal of this review was to gather information about recent publications related to deuterium oxide (D2O), and its use as a scientific tool related to human health. Searches were made in electronic databases Pubmed, Scielo, Lilacs, Medline and Cochrane. Moreover, the following patent databases were consulted: EPO (Espacenet patent search), USPTO (United States Patent and Trademark Office) and Google Patents, which cover researches worldwide related to innovations using D2O. 相似文献
96.
97.
火焰原子吸收分光光度法测定饲料中的铬 总被引:15,自引:1,他引:14
强制性国家标准GB 13078—2001规定了饲料中铬的限量。文章针对饲料中铬含量测定的国家标准方法GB/T 13088—1991的不足,建立了火焰原子吸收分光光度(FAAS)法测定饲料中铬含量的分析方法。分别研究了不同的乙炔流量、燃烧器高度和干扰抑制剂氯化铵的添加量对三价铬[Cr(Ⅲ)]和六价铬[Cr(Ⅵ)]测定灵敏度的影响;比较了用Cr(Ⅲ)和Cr(Ⅵ)标准曲线测定饲料样品中铬的结果,两组测定的平均值经t检验,无显著性差异。FAAS法测定铬的灵敏度为0.014 μg·mL-1;检出限为0.70 mg·kg-1,标准添加回收率为94.4%~104.9%,同一样品重复测定(6~7次)的相对标准偏差(RSD)为1.90%~4.08%。该方法与GB/T 13088—1991相比具有简便、快速、准确等优点,其检出限满足GB 13078—2001规定的饲料中铬的限量要求。 相似文献
98.
Abhishek Rajput Prem P. Sharma Savan K. Raj Jyoti Kumari Mangal S. Rathore Vaibhav Kulshrestha 《Materials Today Chemistry》2021
Desalination of brackish water is a challenging task for higher recovery of water. In most of the cases, water recovery is low with high wastage. Electrodialysis (ED) provides a solution of water desalination with high recovery. Ion-exchange membranes are the main component for electrodialysis system. Here cation-exchange membrane and anion-exchange membrane were synthesized by free-radical polymerization for water desalination by ED. ATR-FTIR confirms the successful functionalization of the membranes and scanning electron microscopy technique reveals the dense morphology of the membranes. Here we used polyethylene as a binder and blow film extrusion for film formation, which is not only economically viable as well as large amount of membranes can be produced without using hazardous solvent. The desalination study reveals the improvement in desalination performance with slight increment in temperature which may be due to higher ionic mobility. The mechanical and thermal stability of the membranes was characterized to ensure the viability of membranes for desalination at higher temperatures. Effect of applied potential was also studied in the removal of pathogens during desalination and confirmed that 2 V/cell pair applied potential removes almost 97% pathogens during desalination in continuous mode. 相似文献
99.
Dr. Debashis Dhara Dr. Scott M. Baliban Dr. Chang-Xin Huo Zahra Rashidijahanabad Dr. Khandra T. Sears Dr. Setare Tahmasebi Nick Dr. Anup Kumar Misra Dr. Sharon M. Tennant Dr. Xuefei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(68):15953-15968
With the emergence of multidrug resistant Salmonella strains, the development of anti-Salmonella vaccines is an important task. Currently there are no approved vaccines against Salmonella Paratyphi A, the leading cause of paratyphoid fever. To fill this gap, oligosaccharides corresponding to the O-polysaccharide repeating units from the surface of Salmonella Paratyphi A have been synthesized through convergent stereoselective glycosylations. The synthetic glycan antigen was conjugated with a powerful immunogenic carrier system, the bacteriophage Qβ. The resulting construct was able to elicit strong and long-lasting anti-glycan IgG antibody responses, which were highly selective toward Salmonella Paratyphi A associated glycans. The availability of well-defined glycan antigen enabled the determination that one repeating unit of the polysaccharide is sufficient to induce protective antibodies, and the paratose residue and/or the O-acetyl modifications on the backbone are important for recognition by antibodies elicited by a Qβ-tetrasaccharide conjugate. Immune sera provided excellent protection to mice from lethal challenge with Salmonella Paratyphi A, highlighting the potential of the synthetic glycan-based vaccine. 相似文献
100.
《Analytical letters》2012,45(7):689-701
Seven water-soluble vitamins: thiamine hydrochloride (B1), riboflavin hydrochloride (B2), pyridoxine hydrochloride (B6), calcium pantotenate (B5), ascorbic acid (C), folic acid (B9), and biotin (H, B7) were separated using the micellar electrokinetic chromatographic (MEKC) method in a single run with the electrolyte solution consisting of 100 mM H3BO3, 5 mM Na2B4O7, and 30 mM sodium dodecylsulphate (SDS). The separation was achieved within 8 min. and the detection was performed at 200 nm. The calibration graphs plotted with six concentrations of each vitamin were linear with the determination coefficient r > 0.999. The method was applied for quantification of vitamins B1, B2, B5, B6, B9, C, and H in novel feed for laboratory animals. The sample preparation involved solid-phase extraction of the vitamins, used prior to the MEKC analysis. The attained precision level was good with the recoveries between 98.4% and 105.6%. The simplicity of the procedure should make it highly useful for feed quality control in husbandry and the animal feed industry. 相似文献