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61.
Despite drug delivery nanoplatforms receiving extensive attention, development of a simple, effective, and multifunctional theranostics nanoplatform still remains a challenge. Herein, a versatile nanoplatform based on a zirconium framework (UiO-66-N3) was synthesized, which demonstrated a combined photodynamic therapy (PDT), photothermal therapy (PTT), and chemotherapy (CT) for cancer treatment. A RuII polypyridyl alkyne complex (Ra) as a photosensitizer was modified into a nanoplatform by click reactions for the first time. When exposed to suitable light irradiation, the as-prepared multifunctional nanoplatform (UiO-Ra-DOX-CuS) not only demonstrated efficient 1O2 generation, but also exhibited excellent photothermal conversion ability. In particular, the nanotherapeutic agent presented a dual-stimuli response; either acidic environment or NIR laser irradiation would trigger the drug release. The synergetic efficacy of UiO-Ra-DOX-CuS combined PDT, PTT, and CT, which was evaluated by cell experiments. Moreover, the design could promote the development of RuII polypyridyl alkyne complexes based multifunctional nanoparticles and multimodal cancer treatment.  相似文献   
62.
为明确低碳政策及道路拥堵对多式联运路径选择的影响,构建了不同碳排放政策下考虑道路拥堵的多式联运路径选择模型。模型在考虑拥堵对运输时间影响的基础上进一步量化其对系统碳排放的作用效果。针对此类整数规划模型,设计了基于保优策略和移民策略的遗传算法进行求解。最后,通过算例探讨强制排放、碳税、碳交易及碳补偿四种碳排放政策对多式联运减排、缓解拥堵及成本的影响。结果表明考虑道路拥堵对运输碳排放的影响可得到更加合理的路径决策,且以强制碳排放政策为主的多种政策组合能更好的降低碳排放、缓解道路拥堵并促进多式联运推广。本模型可为政府制定合理的多式联运低碳政策以及企业制定合理的路径决策提供理论依据。  相似文献   
63.
Contrast agents for magnetic resonance imaging have historically been based on paramagnetic metal complexes, particularly Gd3+ chelates, which tend to lose their contrast enhancement ability with increasing magnetic field strength. Emerging high-field MRI applications require the development of novel contrast agents that exhibit high relaxation enhancement as a function of magnetic field strength. Paramagnetic ions such as Dy3+, Tb3+ or Ho3+ incorporated into supramolecular or inorganic nano-architectures represent promising platforms for the development of high field MRI contrast agents. Furthermore, such platforms allow facile inclusion of multiple imaging modalities, therapeutic loading, and targeting vectors. This Minireview examines the application of contrast agents for high-field MRI, which range from single molecules to nanoparticles. Approaches to create multimodal agents by combining high-field MRI contrast properties with another imaging modality are also discussed.  相似文献   
64.
A method of suppressing the multimodal size distribution of InAs/GaAs quantum dots(QDs) using molecular beam epitaxy through flattening the substrate surface is reported in this work.It is found that the surface roughness plays an important role in the growth of QDs through continuous surface evolution(SEQDs).SEQDs are the main components of small QD ensemble in QDs with multimodal size distribution.It is suggested that most of the SEQDs are very likely to nucleate during the growth interruption rather than...  相似文献   
65.
The benefits to intracellular drug delivery from nanomedicine have been limited by biological barriers and to some extent by targeting capability. We investigated a size‐controlled, dual tumor‐mitochondria‐targeted theranostic nanoplatform (Porphyrin‐PEG Nanocomplexes, PPNs). The maximum tumor accumulation (15.6 %ID g?1, 72 h p.i.) and ideal tumor‐to‐muscle ratio (16.6, 72 h p.i.) was achieved using an optimized PPN particle size of approximately 10 nm, as measured by using PET imaging tracing. The stable coordination of PPNs with 177Lu enables the integration of fluorescence imaging (FL) and photodynamic therapy (PDT) with positron emission tomography (PET) imaging and internal radiotherapy (RT). Furthermore, the efficient tumor and mitochondrial uptake of 177Lu‐PPNs greatly enhanced the efficacies of RT and/or PDT. This work developed a facile approach for the fabrication of tumor‐targeted multi‐modal nanotheranostic agents, which enables precision and radionuclide‐based combination tumor therapy.  相似文献   
66.
视线跟踪技术及其在人机交互中的应用   总被引:21,自引:1,他引:20       下载免费PDF全文
人们在观察外部世界时眼睛总是与其它人体活动自然协调地工作 ,并且眼动所需的认知负荷很 低 ,人眼的注视包含着当前的任务状况以及人的内部状态等信息 ,因此眼注视是一种非常好的能使人机 对话变得简便、自然的候选输入通道.本文介绍了视线跟踪的基本手段、方法和技术 ,对视线跟踪作为人 机交互通道所具有的特点进行了讨论 ,并指出了其在人机交互领域中的应用及前景 .  相似文献   
67.
弹性板振动的多模态主动控制   总被引:2,自引:0,他引:2  
采用多对压电片对板振动的多阶模态进行主动控制。为了改善结构振动控制的效果,本文对选用结构振动能量和控制信号能量作为控制目标函数的LQR控制算法作了初步研究。首先,按能量准则推导了控制目标函数中权系数矩阵(Q矩阵和R矩阵)的理论计算公式,为权系数矩阵的选取提供了一定的理论依据。然后,运用该算法,在研究了单对压电片进行振动主动控制的基础上.本文深入分析了压电层合板振动的多阶模态控制的问题,用Matlab进行系统仿真,得到了压电层合板受到初始位移激励下板中心点的位移和控制电压大小随时间变化的曲线。数值模拟的结果表明,该方法能达到更有效控制结构振动和减小控制能量消耗的目的.进一步验证了该方法能达到有效控制结构振动和减小控制能量消耗的目的。  相似文献   
68.
在显微成像中,对于相位的恢复和定量相位的成像,基于光强传输方程的定量相位成像是一种有效的方法。在沿光轴分布的光强中采集一系列强度图像,利用数值差分估计光强在聚焦面处的一阶轴向微分并通过求解光强传输方程直接得到相位信息。该方法不需要复杂的干涉装置和参考光束,且能够在传统的明场显微镜下实现定量相位成像。近年来,光强传输方程在国内外得到广泛研究和关注,在自适应光学、X射线衍射光学、电子显微学、光学显微成像等领域中显现出巨大的应用前景。本文提出了一种基于光强传输方程的多模式成像系统,将传统的显微镜和计算成像结合起来,赋予了传统显微镜获得定量相位的能力。采用该系统对未染色的花粉粒以及海拉细胞的有丝分裂过程进行了显微观察,验证了系统的多样性与可靠性。  相似文献   
69.
A model of a complicated function under uncertainty is constructed axiomatically, formalizing suppositions on rationality of information on a considered function.  相似文献   
70.
Summary The awesome degree of structural diversity accessible in peptide design has created a demand for computational resources that can evaluate a multitude of candidate structures. In our specific case, we translate the peptide design problem to an optimization problem, and use evolutionary computation (EC) in tandem with docking to carry out a combinatorial search. However, the use of EC in huge search spaces with different optima may pose certain drawbacks. For example, EC is prone to focus a search in the first good region found. This is a problem not only because of the undesirable and automatic rejection of potentially good search space regions, but also because the found solution may be extremely difficult to synthesize chemically or may even be a false docking positive. In order to avoid rejecting potentially good solutions and to maximize the molecular diversity of the search, we have implemented evolutionary multimodal search techniques, as well as the molecular diversity metric needed by the multimodal algorithms to measure differences between various regions of the search space.  相似文献   
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