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71.
《Journal of dairy science》2022,105(3):1966-1977
Aflatoxin M1 (AFM1) is a common toxin in dairy products that causes acute and chronic human health disorders. Thus, the development of a rapid and accurate AFM1 detection method is of vital importance for food safety monitoring. This work was to develop a novel electrochemical aptasensor for sensitive and specific determination of AFM1. The dendritic-like nanostructure was formed on the gold electrode surface by layer-by-layer assembly of gold-silver core-shell nanoparticles modified with DNA conjugates. In the presence of AFM1, the specific recognition between AFM1 and Apt caused the disassociation of the DNA controlled dual Au@Ag conjugates from the surface of the electrode, causing less methylene blue to bind to the surface and weakening the electrochemical signal. The more AFM1 there is, the weaker the electrochemical signal. Transmission electron microscope results showed that the successfully synthesized Au@Ag nanoparticles exhibited a core-shell structure with Au as core and Ag as shell, and their average diameter was about 30 nm. Under optimal conditions, the electrochemical aptasensor showed a wide detection ranging from 0.05 ng mL?1 to 200 ng mL?1, and a low detection limit of 0.02 ng mL?1. Moreover, the proposed strategy has been successfully applied to the detection of AFM1 in cow, goat, and sheep milk samples with satisfactory recoveries ranging from 91.10% to 104.05%. This work can provide a novel rapid detection method for AFM1, and also provide a new sensing platform for the detection of other toxins. 相似文献
72.
Hai Chi Yujie Li Guoqin Liu 《International Journal of Food Science & Technology》2022,57(8):5376-5387
In this study, a new electrochemical strategy based on the fabrication of a molecularly imprinted sensor onto a MoS2-loaded peanut shell carbon complex with gold nanoparticles (AuNPs) and nitrogen-doped carbon dots (N-CDs) was proposed for the detection of benzo(a)pyrene (BaP). Molecularly imprinted polymer (MIP) films were prepared by cyclic voltammetry (CV) using 2-mercaptobenzimidazole (2-MBI) as a functional monomer in the presence of BaP. The surface morphologies, structural characteristics and electrochemical properties of the obtained MIP/AuNPs/N-CDs/PSBC/MoS2/GCE were investigated via scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectrometry (EDS), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), UV–Vis spectrometry, fluorescence spectrometry, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimised conditions, the detection range of the electrode towards BaP varied from 5 nM to 20 μM with a detection limit of 1.5 nM. The prepared electrochemical sensor also exhibited good stability, relevant reproducibility and high selectivity. The application of the sensor in the actual analysis of edible oil samples showed promising results, thereby being relevant as a biomimetic sensing platform for the detection of chemical hazards in food and environment. 相似文献
73.
74.
1IntroductionLithium secondary batteries have been rapidly developed because of their well performances such ashigh voltage,high specific energy,high capacity and light weight since appeared at last century.It waspromising to be the main power source of electric vehicles and electric tools.The more practical interestcathode materialsincluded mainlylithiumcobalt oxide,lithiumnickel oxide andlithium manganese oxideetal.At present,lithiumcobalt oxygen was the most widely usedin comerical,andits s… 相似文献
75.
硅掺杂对贮氢电极合金Ml(Ni,Co,Mn,Ti)5电化学性能的影响 总被引:1,自引:0,他引:1
针对混合稀土金属中含有不定量的硅杂质及贮氢电极合金在熔炼过程中容易混入硅杂质的特点,通过在Ml(Ni,Co,Mn,Ti)5合金中人为地添加不同量硅的方法,系统地研究了硅掺杂对贮氢电极合金Ml(Ni,Co,Mn,Ti)5电化学性能的影响。结果表明,硅掺杂量增加,会降低合金的放电容量;随着硅掺杂量的增加,合金的活化性能降低;当硅掺杂量从0增至0.15时,合金的循环稳定性逐渐提高,但当硅掺杂量进一步增加时,循环稳定性逐渐降低。 相似文献
76.
77.
利用电化学阻抗方法研究了球形氢氧化镍电极的等效电路特征及其与电极荷电状态的变化规律。不同荷电状态的交流阻抗行为虽基本可用Randles电路来描述,但双电层电容和Warburg阻抗用常相角元件代替更加符合实际电极的情况。应用数理统计方法研究表明:在高荷电状态时电化学反应界面上可能存在不同于低荷电态时的较强的质子吸附。电荷转移电阻在低荷电情况下变化不明显,但在高荷电时明显增大;电极活化后比活化前,尤其高荷电态比低荷电态质子扩散阻抗激剧减小,满荷电态时的质子转移电阻约相当于活化前的1/10。 相似文献
78.
论述了给水钢管外腐蚀的原因,并就采用阴极保护技术来防止给水钢管外腐蚀的具体措施进行了介绍,指出在使用阴极保护措施的同时应重视管壁保护涂层的作用。 相似文献
79.
硫代硫酸钠脱氯特性及其动力学分析 总被引:3,自引:0,他引:3
考察了二级生物处理出水经氯消毒后采用硫代硫酸钠脱氯的效果。结果表明,在氯消毒后初始余氯为10mgCl2/L的条件下,当反应时间为60min、硫代硫酸钠投量由理论投加量的100%增加至500%时,余氯去除率由41.2%增加到95.5%。硫代硫酸钠脱氯过程为分步反应:在最初的1min内,余氯脱除速率最快;反应1min后,自由氯脱除呈现零级反应,一氯胺、有机氯胺为一级反应;自由氯脱除速度快于一氯胺和有机氯胺,无机氯胺和有机氯胺是硫代硫酸钠脱氯反应速率的限制因素。当以硫代硫酸钠作为脱氯剂时,采用普通活性污泥法的污水处理厂需通过提高硫代硫酸钠投加量来实现快速脱氯,而采用生物脱氮工艺且硝化效果良好的污水处理厂只要保证足够的脱氯反应时间即可实现很好的脱氯效果。 相似文献
80.
An electrochemical model for an upflow dual-chambered microbial fuel cell (MFC) process is proposed in this study. The model was set up on the basis of the experimental results and the analysis of biochemical and electrochemical processes in the MFC biocatalysed with anaerobic aged sludge and alternatively fuelled with a synthetic acetate-based and actual domestic wastewaters. Simulation of the process shows that the model describes the process reasonably well with correlation coefficients higher than 0.97. The analysis of model simulation illustrates how the current output depends mainly on the substrate concentration as well as other main variables. The relationship between the current output and over-voltage is revealed by the modelling study. For acetate-based wastewaters with initial chemical oxygen demand (COD) concentrations of 350, 700, 1050, and 1400 mg/L, maximum observed power densities were 290, 405, 448, and 525 mW/m2 associated with maximum COD removals of 84%, 88%, 83%, and 82%, respectively. 相似文献