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131.
Phase transition from WO3 to sub‐stoichiometric WO2.9 by a facile method has varied the typical semiconductor to be quasi‐metallic with a narrowed band gap and a shifted Femi energy to the conduction band, while maintaining a high crystallinity. The resultant WO2.9 nanorods possess a high total absorption capacity (ca. 90.6 %) over the whole solar spectrum as well as significant photothermal conversion capability, affording a conversion efficiency as high as around 86.9 % and a water evaporation efficiency of about 81 % upon solar light irradiation. Meanwhile, the promising potential of the nanorods for anticancer photothermal therapy have been also demonstrated, with a high photothermal conversion efficiency (ca. 44.9 %) upon single wavelength near‐infrared irradiation and a high tumor inhibition rate (ca. 98.5 %). This study may have opened up a feasible route to produce high‐performance photothermal materials from well‐developed oxides.  相似文献   
132.
New quinoxaline-based organic sensitizer bearing di-anchoring group for dye-sensitized solar cells (DSSCs) was synthesized from diethyl 4,5-diaminophthaltate, in which was prepared under mild condition by using Takehito’s method. The synthesized sensitizer was compared with mono-anchoring sensitizer through absorption spectra, emission spectra, J-V curve, and IPCE spectra, indicating the di-anchoring group leads to a noticeable improvement of Jsc value owing to more efficient intramolecular charge transfer and channel number increment.  相似文献   
133.
A star-shaped electron acceptor with porphyrin as core and rhodanine-benzothiadiazole as end groups linked with ethynyl units was developed for non-fullerene solar cells, in which a PCE of 1.9% with broad photo response was achieved when combining with a diketopyrrolopyrrole-polymer as electron donor.  相似文献   
134.
A homopolymer based on double B ← N bridged bipyridine was reported as a novel polymer electron acceptor. The resulting all-polymer solar cells show power conversion efficiencies of 2.44%–3.04%.  相似文献   
135.
Cancer stem cells (CSCs) have been shown to be refractory to conventional therapeutic agents, can promote metastasis, and have been linked to cancer relapse. Salinomycin can selectively kill CSCs. We have shown that salinomycin derivatives accumulate in lysosomes and sequester iron in this organelle. As a result, accumulation of iron leads to the production of reactive oxygen species and lysosomal membrane permeabilization, which in turn promotes cell death by ferroptosis. These findings have revealed the prevalence of iron homeostasis in CSCs and paved the way toward the development of next-generation therapeutics.  相似文献   
136.
核壳结构碳化钨复合微球催化剂对甲醇电催化性能   总被引:1,自引:0,他引:1  
以偏钨酸铵微球为前驱体,在不同反应时间和CO/CO2气氛条件下,通过原位还原碳化反应制备了具有核壳结构碳化钨复合微球。采用X射线粉末衍射(XRD)、X射线光电子能谱(XPS)和扫描电镜(SEM)等对催化剂的形貌和结构进行了表征分析。硼氢化钠还原法将平均粒径为4.6 nm的Pt纳米粒子均匀分布在其表面,得到核壳结构碳化钨复合催化剂。采用循环伏安和计时电流法研究了在酸性溶液中催化剂对甲醇的电催化氧化性能。结果表明,与Pt/WC-15 h和JM Pt/C催化剂的电化学性能相比,Pt/WC-6 h催化剂对甲醇呈现出更高的电催化氧化活性和稳定性。碳化钨复合微球表面少量WO2成分的存在有利于甲醇在其表面的电催化氧化过程的发生。  相似文献   
137.
5-Formyl-2-thiopheneboronic acid is a widely used building block for the synthesis of diverse structures, however, due to a significant instability its transformation to 5-arylthiophene-2-carboxaldehydes by CC couplings could be performed only in low yields. Herein, as a solution, a convenient technique is described for the preparation of 1,3-dioxolane-protected 5-arylthiophene-2-carboxaldehydes via a one-pot borylation–copper(I) chloride co-catalyzed Suzuki-Miyaura coupling reaction. The utilization of the in situ prepared 2-thiopheneboronic ester derivative is allowed by the method developed. Elimination of the crucial, acidic liberation step of boronic acid species resulted in improved yields and purities. In addition, comparison of various aryl bromides is shown to demonstrate the high tolerance of the transformation to functional groups.  相似文献   
138.
Herein, we report use of [Li+@C60]TFSI? as a dopant for spiro‐MeOTAD in lead halide perovskite solar cells. This approach gave an air stability nearly 10‐fold that of conventional devices using Li+TFSI?. Such high stability is attributed to the hydrophobic nature of [Li+@C60]TFSI? repelling moisture and absorbing intruding oxygen, thereby protecting the perovskite device from degradation. Furthermore, [Li+@C60]TFSI? could oxidize spiro‐MeOTAD without the need for oxygen. The encapsulated devices exhibited outstanding air stability for more than 1000 h while illuminated under ambient conditions.  相似文献   
139.
This study presents the preparation of graphene (GR) nanocomposites with polyaniline (PANI) and polypyrrole (PPy) through the fast, versatile and environmentally friendly process of radio frequency (RF)-plasma polymerization. Morphological characterization of the nanocomposites is performed using scanning electron microscopy (SEM) and shows that the PANI and PPy conducting polymers coated the GR surface. The surface properties of the GR nanocomposites are determined using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). The prepared GR nanocomposites are then used as counter electrodes in dye-sensitized solar cells (DSSCs). The conversion cell efficiencies for iodine-doped DSSC samples are found to be 0.086%, 5.41%, and 5.60% for I2-PANI, I2-PANI-GR and I2-PPy-GR, respectively, while the corresponding undoped samples reaches power conversion efficiencies of 3.82%, 1.30%, and 0.077% for PPy-GR, PANI-GR and PANI, respectively. The incident photon-to-current efficiency (IPCE) of iodine-doped composite-based DSSCs is significantly enhanced.  相似文献   
140.
喹喔啉衍生物由于合成简单,易功能化,成本较低等特点在众多领域都有广泛应用。其自身具有平面刚性结构,也是构建光电聚合物的重要单体。基于喹喔啉单元的有机分子化学结构和电子结构可修饰性强,通过骨架、侧链和取代基等修饰,易于调控分子的能级和吸光光谱,因此,当使用喹喔啉体系的共轭给体与球形富勒烯受体(如PCBM)及弱结晶性非富勒烯受体(如ITIC)均可表现出优异的光伏性能。在本工作中,基于结晶性较强的非富勒烯受体(o-IDTBR),我们首次制备出侧链不对称喹喔啉(简称:不对称喹喔啉)基聚合物(TPQ-1)与之匹配。相比于侧链对称性喹喔啉(简称:对称喹喔啉)(HFQx-T)与o-IDTBR组合,“弱结晶给体-强结晶受体”组合能表现出更佳均匀的相分离尺度,从而获得更高的短路电流及能量转换效率。TPQ-1与o-IDTBR共混后器件效率为8.6%,加入15%的TB7-Th后,器件效率达到9.6%。  相似文献   
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