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61.
结核菌H37Ra在小鼠体内诱导的免疫应答 总被引:1,自引:0,他引:1
目的检测结核菌H37Ra免疫小鼠后产生的特异性细胞免疫和体液免疫应答水平。方法将BALB/c小鼠随机分为H37Ra组、BCG组和生理盐水(NS)组,分别进行免疫,免疫8周后处死小鼠,分离血清,ELISA间接法测定血清特异性抗PPDIgG抗体的水平,流式细胞分析仪检测脾脏T淋巴细胞亚群的变化。脾淋巴细胞经体外培养、PPD刺激后,MTT法检测脾淋巴细胞的刺激指数,ELISA法检测培养上清液中IFN-γ和IL-4的水平。结果H37Ra免疫小鼠血清中抗PPDIgG抗体、脾脏CD3+T细胞和CD4+T细胞的百分率、脾淋巴细胞刺激指数、IFN-γ和IL-4水平均显著高于NS对照组,但与BCG组差异无显著意义。各组间脾脏CD8+T细胞、CD4+T/CD8+T比值差异均无显著意义。结论H37Ra免疫小鼠后,可以产生特异性的细胞免疫和体液免疫应答,有望成为结核疫苗的候选抗原。 相似文献
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63.
The aim of this study was to assess the biopotency of fermented food product Koozh associated coagulase-negative staphylococci (CNS) against Mycobacterium tuberculosis H37Rv and non-mycobacterial pathogens, and to document some technologically relevant attributes. The anti-tubercular property of six CNS strains was exhibited using luciferase reporter phage assay. All strains revealed pronounced mycobactericidal property in terms of higher percentage of relative light unit reduction (> 90%). The antagonistic role of CNS strains against non-mycobacterial pathogens was evaluated using agar well diffusion assay. Staphylococcus hominis strain MANF2 was found to be the most effective against Staphylococcus aureus MTCC 96 and Yersinia enterocolitica MTCC 840 with arbitrary units of 1600.31 ± 22.3 and 1500.23 ± 22.3 AU/mL, respectively. Further, various technological attributes of staphylococci were determined using standard methodology. All strains exhibited promising carbohydrate fermentation ability at standard in vitro conditions. CNS strains were positive for exopolysaccharide production and expressed strain specific lipase activity. All the isolates lacked amylase activity and biofilm formation ability. All six CNS strains, particularly strain MANF2 exhibited significant rate of autolytic and catalase activity, and showed the potential to reduce nitrate to nitrite. Most importantly, these strains were categorized for safe utilization based on in vitro safety hazards test. Overall, the present investigation indicated the persuasive biopotency of CNS against M. tuberculosis H37Rv and non-mycobacterial pathogens, and revealed adaptable technological attributes that would make them relevant for formulation of staphylococcal starter cultures for the development of quality fermented food products. 相似文献
64.
为提高继电保护装置的光纤通道故障监测能力和定位能力,尝试将IEEE-C37.94光接口标准应用到继电保护装置,并研究该标准应用到继电保护装置中的优势及局限性。通过解读IEEE-C37.94光接口标准帧格式的协议,结合国内继电保护装置的光纤传输要求,验证该标准可以允许不同厂家的保护设备与数字复接接口设备在光接口处能够互通,并且对不同链路的通信故障能够有效定位。但也存在传输带宽不高问题,宽松的校验措施也给其应用于继电保护设备带来了一些局限性。实际应用情况表明,IEEE-C37.94标准应用于继电保护设备是可行的。 相似文献
65.
分析了SP 800-37的版本演变过程,解读了SP 800-37:2010版的主要内容,重点研究了风险管理框架的六个步骤及其相关任务。 相似文献
66.
A. Tunyogi F. Tanczikó F. Pászti 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(22):4916-4920
Fe/Ag thin films are intensively investigated due to their special magnetic properties. Recently a deposition-order dependent asymmetric interface has been found. When iron is grown on silver, the interface is sharp, while the growth of Ag on Fe results in a long, low-energy tail of the Ag peak in the Rutherford backscattering spectrometry (RBS) spectra. The main purpose of this paper is to show that the low-energy Ag tail is caused by grain boundary diffusion, and that, when elevating the growing temperature of the Ag layer this effect becomes more significant. Two sets of polycrystalline and epitaxial Fe/Ag bilayers were prepared simultaneously onto Si(1 1 1) and MgO(1 0 0), respectively. The iron layers were grown at 250 °C and annealed at 450 °C in both sets, while the Ag layer was grown in the first set at room temperature (RT) and in the second set at 250 °C (HT). The sample composition, the interface sharpness and the quality of the epitaxy were studied by Rutherford backscattering spectrometry (RBS) combined with channeling effect. The surface morphology was determined by atomic force microscopy (AFM). RBS spectra show that in the case of RT samples the epitaxial MgO/Fe/Ag bilayer has sharp, well-defined interface, while for the polycrystalline Si/Fe/Ag sample the silver peak has a low-energy tail. Both the Fe and Ag peaks smeared out in the case of HT samples. AFM-images show that the RT samples have a continuous Ag layer, while the HT samples have fragmented surfaces. The RBS spectra taken on the HT samples were successfully simulated by the RBS-MAST code taking into account their fragmented structures. 相似文献
67.
Rashi Nathawat Anil Kumar Y.K. Vijay D. Kanjilal 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(21):4749-4756
Polyethyleneterephthalate (PET) has been modified by 100 keV Ni+ and N+ ions using metal ion from volatile compound (MIVOC) ion source to fluence ranging from 1 × 1014 to 1 × 1016 ions/cm2. The increasing application of polymeric material in technological and scientific field has motivated the use of surface treatment to modify the physical and chemical properties of polymer surfaces. When a material is exposed to ionization radiation, it suffers damage leading to surface activation depending on the type. The surface morphology was observed by atomic force microscopy (AFM). That show the roughness increases with fluence in both the cases. The Ni particles as precipitation in PET were observed by cross-section transmission electron microscopy (XTEM). The optical band gap (Eg) deduced from absorption spectra; was calculated by Tau’c relation. Raman spectroscopy shows quantitatively the chemical nature at the damage caused by the Ni+ and N+ bombardment. The ration of ID/IG shows graphite-like structure is formed on the surface. A layer of hydrogenated amorphous carbon is formed on the surface, which has confirmed by XPS results also. 相似文献
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69.
A. Moses Ezhil Raj R. Ravishankar G. Selvan C. Sanjeeviraja 《Materials Research Bulletin》2009,44(5):1051-9430
Transparent conducting magnesium indium oxide films (MgIn2O4) were deposited on to quartz substrates without a buffer layer at an optimized deposition temperature of 450 °C to achieve high transmittance in the visible spectral range and electrical conductivity in the low temperature region. Magnesium ions are distributed over the tetrahedral and octahedral sites of the inverted spinel structure with preferential orientation along (3 1 1) Miller plane. The possible mechanism that promotes conductivity in this system is the charge transfer between the resident divalent (Mg2+) and trivalent (In3+) cations in addition to the available oxygen vacancies in the lattice. A room temperature electrical conductivity of 1.5 × 10−5 S cm−1 and an average transmittance >75% have been achieved. Hall measurements showed n-type conductivity with electron mobility value 0.95 × 10−2 cm2 V−1 s−1 and carrier concentration 2.7 × 1019 cm−3. Smoothness of the film surface observed through atomic force microscope measurements favors this material for gas sensing and opto-electronic device development. 相似文献
70.
In this paper, a simple and environmentally friendly electroless plating solution of chloroauric acid (HAuCl4) and hydrogen peroxide (H2O2) for depositing gold film onto (3-aminopropyl)-trimethoxysilane (APTMS) -coated glass surface has been developed. APTMS as an adhesive reagent was used to attach the gold nanoparticles (AuNPs) onto the glass substrate. These AuNPs could be regarded as the preferential nucleation or catalytic sites for gold electroless reduction, which accelerated the reduction of Au3+ on the glass surface and effectively prevented the formation of gold metal in the bulk solution. During the gold plating process, H2O2 as the reducing agent was thermodynamically capable of reducing Au3+ ions from the HAuCl4 precursor to gold atoms, which deposited onto the glass surface and finally formed the continuous gold film. The resulting gold film was characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and atomic force microscope (AFM), respectively. 相似文献