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91.
The controllable oxidation of spiro‐OMeTAD and improving the stability of hole‐transport materials (HTMs) layer are crucial for good performance and stability of perovskite solar cells (PSCs). Herein, we report an efficient hybrid polyoxometalate@metal–organic framework (POM@MOF) material, [Cu2(BTC)4/3(H2O)2]6[H3PMo12O40]2 or POM@Cu‐BTC, for the oxidation of spiro‐OMeTAD with Li‐TFSI and TBP. When POM@Cu‐BTC is introduced to the HTM layer as a dopant, the PSCs achieve a superior fill factor of 0.80 and enhanced power conversion efficiency 21.44 %, as well as improved long‐term stability in an ambient atmosphere without encapsulation. The enhanced performance is attributed to the oxidation activity of POM anions and solid‐state nanoparticles. Therefore, this research presents a facile way by using hybrid porous materials to accelerate oxidation of spiro‐OMeTAD, further improving the efficiency and stability of PSCs.  相似文献   
92.
阶梯型加速段对旋流喷嘴雾化特性的影响   总被引:1,自引:1,他引:0  
旋流内芯是压力旋流式喷嘴最主要的旋流发生构件, 其几何特征直接影响压力旋流式喷嘴的喷雾特性.目前采用平滑型加速段的旋流内芯导流效率较低.为减小高流量条件下的能量损失, 使喷嘴旋流内芯加速段对喷雾介质产生预旋效应, 增强旋流强度, 本文设计喷嘴旋流内芯加速段为阶梯型, 其下段阶梯相对上段阶梯旋转15°, 旋向与喷嘴旋流槽方向相同.利用粒子动态分析仪(particle dynamics analysis system, PDA) 和高速摄影(charge coupled device, CCD)系统实验研究了加速段结构改进前后喷嘴的喷雾流量、雾场索特尔平均直径(Sauter mean diameter, SMD)、雾滴速度以及喷雾锥角, 并分析了SMD、 雾滴速度的轴向和径向分布特性. 结果表明, 背压差0.08~ 0.46 MPa 范围内, 阶梯型加速段对喷雾介质具有较好的预旋效果.喷嘴的流量提高了48.0% ~ 51.8%; 喷雾的轴向速度提升了31.4% ~ 32.8%, 径向速度提升了1.6% ~ 16.8%; 喷雾锥角减小了4.21°~6.57°; 较高背压差下喷雾下游的SMD减小了9.8%.与平滑型加速段相比, 阶梯型加速段的设计有效地提高了喷嘴的雾化质量.   相似文献   
93.
针对不同贮存时长三氢化铝醚合物能否转晶制备α-三氢化铝问题进行了深入研究。 本文采用传统法制得三氢化铝醚合物并在氮气气氛下储存1~20 d,然后基于此三氢化铝醚合物,采用固相、真空转晶技术制备α-三氢化铝。 X射线衍射(XRD)、热重分析(TGA)和扫描电子显微镜(SEM)分析表明,随着醚合物贮存时间的延长,其乙醚成分逐渐降低,贮存10 d仍然可以制备出纯度较高的α-三氢化铝,然而10 d后,有γ-三氢化铝产生,而且产物粒径变小。 证明醚合物中乙醚的含量多少与制备出的α-三氢化铝的品质有直接关联。 制备过程摒弃有毒试剂甲苯,也为α-三氢化铝的千克级制备提供了一种可能。  相似文献   
94.
In this work, three organosilica precursors functionalized with carbamate moieties were synthesized by condensing of 3‐isocyanatopropyltriethoxysilane and coupling regents of either hydroquinone (HQ), bisphenol A (BPA), or 1,1′‐bi‐2‐naphthol (BN). These organosilica precursors were covalently bonded in the framework of periodic mesoporous organosilicas by co‐condensation and hydrolysis with tetraethyl orthosilicate (TEOS) under hydrothermal treatment. The compositions and physical properties were characterized with FTIR, XRD, thermogravimetric/differential thermal analysis (TG/DTA), 29Si NMR, 13C NMR spectroscopies, SEM, TEM, and BET technologies. These characterizations suggest that three different structures were formed as the result of different sizes and compositions of the organosilica precursors. The three mesoporous organosilicas were applied as heterogeneous catalysts in the one‐pot cascade Knoevenagel and Michael cyclopropanic reactions for the synthesis of cyclopropanic derivatives and showed excellent activity and selectivity. The highest conversion was obtained with mesoporous catalyst (MC)‐HQ owing to its ordered mesostructure, highest surface area, and weakest stereo effect of the organic linking groups compared with MC‐BAP and MC‐BN. This methodology employed cheaper and more easily obtainable raw materials as reagents over the traditional alkene additive system and these heterogeneous catalysts exhibit superior performance and recyclability than typical homogeneous organic catalysts.  相似文献   
95.
A carbonation process for the synthesis of active super-fine calcium carbonate particles from Ca(OH)(2) slurry at room temperature using a CO(2)-N(2) gas mixture was investigated. Industrial octadecyl dihydrogen phosphate (A) was added as a size-controlling additive and modifier in different reaction periods according to the pH of the medium. Analysis of the reaction products led to the conclusion that the addition of A in the digestion period could inhibit the crystal growth of calcium carbonate, while the addition of A at pH 7 of the medium could modify the surface character of the calcium carbonate particle, which was found to exhibit hydrophobic properties. From transmission electron microscopy (TEM), the hydrophobic property was attributed to the deposition of calcium alkyl phosphates, produced in the reaction mixture, onto the surface of calcium carbonate particle. IR spectra and TGA analysis of the obtained products indicated that A was bound onto the crystalline CaCO(3).  相似文献   
96.
Fidelity is a fundamental and ubiquitous concept in quantum information theory. Fuchs–van de Graaf’s inequalities deal with bounding fidelity from above and below. In this paper, we give a lower bound on the quantum fidelity between two states in terms of their trace-distance and their max-relative entropy.  相似文献   
97.
A yolk–shell-structured sphere composed of a superparamagnetic Fe3O4 core and a carbon shell (Fe3O4@HCS) was etched from Fe3O4@SiO2@carbon by NaOH, which was synthesized through the layer-by-layer coating of Fe3O4. This yolk–shell composite has a shell thickness of ca. 27 nm and a high specific surface area of 213.2 m2 g?1. Its performance for the magnetic removal of tetracycline hydrochloride from water was systematically examined. A high equilibrium adsorption capacity of ca. 49.0 mg g?1 was determined. Moreover, the adsorbent can be regenerated within 10 min through a photo-Fenton reaction. A stable adsorption capacity of 44.3 mg g?1 with a fluctuation <10% is preserved after 5 consecutive adsorption–degradation cycles, demonstrating its promising application potential in the decontamination of sewage water polluted by antibiotics.  相似文献   
98.
Silica nanotubes were synthesized from kaolin clay using surfactant intercalation, sulfuric acid and hydrothermal treatments.  相似文献   
99.
Hybrid organic-inorganic compounds have attracted increasing interest in recent years due to the possibility of combination of different characteristics of the compounds to get unusual structures, properties, or applications1. Polyoxometalates (POMs) whic…  相似文献   
100.
Synthetic fluorescent protein chromophores have been reported for their singlet state fluorescence properties and applications in bioimaging, but rarely for the triplet state chemistries. Herein, we enabled their photo-sensitizing and photo-crosslinking properties through rational modulations. Extension of molecular conjugation and introduction of heavy atoms promoted the generation of reactive oxygen species. Unlike other photosensitizers, these chromophores selectively photo-crosslinked aggregated proteins and uncovered the interactome profiles. We also exemplified their general applications in chromophore-assisted light inactivation, photodynamic therapy and photo induced polymerization. Theoretical calculation, pathway analysis and transient absorption spectroscopy provided mechanistic insights for this triplet state chemistry. Overall, this work expands the function and application of synthetic fluorescent protein chromophores by enabling their triplet excited state properties.  相似文献   
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