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91.
Photodynamic therapy (PDT) agent, which generates singlet oxygen (1O2) under light, has attracted significant attention for its broad biological and medical applications. Here, DNA‐driven shell–satellite (SS) gold assemblies as chiral photosensitizers are first fabricated. The chiral plasmonic nanostructure, coupling with cysteine enantiomers on its surface, exhibits intense chiroplasmonic activities (?40.2 ± 2.6 mdeg) in the visible region. These chiral SS nanoassemblies have high reactive oxygen species generating efficiency under circular polarized light illumination, resulting in a 1O2 quantum yield of 1.09. Meanwhile, it is found that SS could be utilized as PDT agent with remarkable efficiency under right circular polarized light irradiation in vitro and in vivo, allowing X‐ray computed tomography (CT) and photoacoustics (PA) imaging for tumors simultaneously. The achievements reveal that the enantiomer‐dependent and structure‐induced nanoassemblies play an important role in PDT effects. The present researches open up a new avenue for cancer diagnose and therapy using chiral nanostructures as multifunctional platform.  相似文献   
92.
Assemblies of nanomaterials for biological applications in living cells have attracted much attention. Herein, graphene oxide (GO)–gold nanoparticle (Au NP) assemblies are driven by a splint DNA strand, which is designed with two regions at both ends that are complementary with the DNA sequence anchored on the surface of the GO and the Au NPs. In the presence of microRNA (miR)‐21 and epithelial cell‐adhesion molecule (EpCAM), the hybridization of miR‐21 with a molecular probe leads to the separation of 6‐fluorescein‐phosphoramidite‐modified Au NPs from GO, resulting in a decrease in the Raman signal, while EpCAM recognition reduces circular dichroism (CD) signals. The CD signals reverse from negative in original assemblies into positive when reacted with cells, which correlates with two enantiomer geometries. The EpCAM detection has a good linear range of 8.47–74.78 pg mL?1 and a limit of detection (LOD) of 3.63 pg mL?1, whereas miR‐21 detection displays an outstanding linear range of 0.07–13.68 amol ng?1RNA and LOD of 0.03 amol ng?1RNA. All the results are in good agreement with those of the Raman and confocal bioimaging. The strategy opens up an avenue to allow the highly accurate and reliable diagnosis (dual targets) of clinic diseases.  相似文献   
93.
As an emerging treatment for cancer, phototherapy has received much clinical attention. Here, a multifunctional Au nanocup (Au NC) for the targeted computed tomographic and photoacoustic imaging of cancerous tumors and phototherapy is reported. The Au NC has an intrinsic photothermal conversion efficiency of 38.5% and offers a tumor‐specific targeted computed tomographic and photoacoustic imaging system. Furthermore, when treated with nontoxic Au NC‐Ce6, cancer cells and tumors are obliterated with low doses of irradiation and safe power levels, with both photothermal and photodynamic therapeutic effects, in vitro and vivo. These data provide a solid foundation for the clinical application of Au NC.  相似文献   
94.
Nanomaterials with high biocompatibility and efficient photothermal conversion have drawn tremendous attention for tumor diagnosis and treatment. In this study, spiky Fe3O4@Au supraparticles (SPs) are used as phototherapy and multimodal imaging agents. The SPs show excellent photothermal and photodynamic therapeutic effects, with a photothermal conversion efficiency of 31%, and allow tumor‐targeted imaging, including computed tomographic, photoacoustic, and magnetic resonance imaging. The SPs show excellent biocompatibility both in vitro and in vivo. Furthermore, because of their remarkable absorption at near‐infrared region, the SPs obliterate a tumor under 808 nm irradiation. With their capacity for highly integrated multimodal imaging and multiple therapeutic functions, SPs are a promising agent for application to clinical practice.  相似文献   
95.
配电网发生故障后,迅速利用大量的告警信息判别出故障元件,能为调度中心的工作人员提供重要的决策支持。针对现有Petri网的故障诊断方法未应用在配电网中的问题,提出了一种时间约束的改进分层模糊Petri网的配电网故障诊断方法。对配电网中的可疑故障元件建立改进的分层模糊Petri网模型,能够适应网络拓扑结构的变换,利用获得的报警信息通过反向和正向时序推理对保护和断路器进行时序检查,对不满足时间约束的库所进行置信度修正。给出了改进分层模糊Petri网模型的推理流程及矩阵推理算法,在矩阵推理过程中引入高斯函数修正概率,使概率始终保持在0~1,最终得到故障元件的置信概率及其时间点约束。通过对配电网系统算例的比较、分析,验证了所提方法的正确性和合理性,能够有效地诊断出配电网的故障元件。  相似文献   
96.
基于神经网络的轮胎硫化过程建模及模糊控制   总被引:6,自引:0,他引:6  
本文利用基于BP算法的人工神经网络,加入移动窗口技术和回流技术,建立轮胎硫化过程的动态温度分布模型,所建立的模型与实际拟合良好,具有实用性。为保证轮胎内部各部分达到均匀一致的硫化效果,根据模糊控制的思想用脉冲加热控制方式得到了满意的控制效果。  相似文献   
97.
一类时滞系统的模型参考自适应控制   总被引:8,自引:0,他引:8  
模型参考自适应控制系统已较广泛地应用于工业过程,其设计方法有的比较成熟,有的还正在发展,有待完善〔1〕。模型参考自适应控制系统的设计关键在于参考模型的给出。本文针对实际过程的特点,将一些复杂高阶系统简化为一类时滞系统。(即:一阶加纯滞后或二阶加纯滞后),并且提出了时滞系统的模型参考自适应控制的设计方法。仿真证明,该方法设计的自适应控制系统具有很好的鲁棒性,可广泛地应用于一般过程控制取代PID控制器。  相似文献   
98.
We designed and synthesized novel haptens to produce monoclonal antibodies(mAb)against vitamin B6(VB6).A group-specific mAb(2F9)that recognized pyridoxine(PN),p...  相似文献   
99.
In this study, yellow, red and purple potato starches were selected as the research objects to analyse the fine structure and the relation to the physicochemical properties. Enzymatic hydrolysis and high-performance anion-exchange chromatograph were employed to characterise the structure of clusters and φ, β-limit dextrins. The average degree of polymerisation of clusters from the yellow potato starch was larger (188.57) than in red (91.31) and purple (107.32) potato starch. The molar percentage of fingerprint B chains in yellow, red and purple potato amylopectin were 58.01%, 63.60% and 60.78%, respectively, while major part of short B chains were 15.92%, 17.16% and 16.49%, respectively. The yellow potato amylopectin showed the highest density of branches values indicated that it was more tightly branched. The Pearson correlation coefficients results indicated that the fine structure of amylopectin had significant effects on the physicochemical properties of potato starches, and we can better understanding the differences of the properties among the three potato starches by studying the amylopectin fine structure.  相似文献   
100.
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