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261.
Chunyu Xu Ke Jin Zuo Xiao Zijin Zhao Xiaoling Ma Xuelin Wang Junming Li Wenjing Xu Shuping Zhang Liming Ding Fujun Zhang 《Advanced functional materials》2021,31(52):2107934
Wide bandgap polymer D18 with narrow photon harvesting in visible light range and small molecule N3 with near-infrared photon harvesting are adopted for building semitransparent organic photovoltaics (OPVs). To find out the optimal D18:N3 weight ratio for semitransparent OPVs, series of opaque OPVs are built with a varied D18:N3 weight ratio. The power conversion efficiency (PCE) and fill factor can be maintained over 16% and 77% in the D18:N3 (0.7:1.6, wt/wt) based opaque OPVs, respectively. The average visible transmittance (AVT) of the corresponding blend films can be achieved over 50%, demonstrating the great potential in fabricating efficient semitransparent OPVs. The semitransparent OPVs based on D18:N3 (0.7:1.6, wt/wt) are fabricated by using 1 nm Au/(10, 15, 20 nm) Ag as cathode. The thickness of Ag layers is varied to balance the optical properties and electrical properties of semitransparent top electrode. The semitransparent OPVs with 10 nm Ag achieve the highest light utilization efficiency of 2.90% with a PCE of 12.91% and an AVT of 22.49%, which should be among the best performance of reported semitransparent OPVs. This work demonstrates that the wide bandgap polymer donor with narrow photon harvesting in visible light range has great potential in preparing efficient semitransparent OPVs. 相似文献
262.
为了发展高性能、低成本和结构简单的ZnO纳米 器件,在本文中,利用简便的热分解法,在p型 硅(p-Si)基底上制备ZnO纳米晶薄膜,利用场发射扫描电子显微镜(FESEM)、X射线衍射仪 (XRD)、紫外- 可见分光光度计和荧光光谱仪,分别研究了ZnO纳米晶薄膜的形貌、晶相结构和光学特性。 结果显示:在 p-Si基底上形成不规则颗粒状ZnO纳米晶,为多晶六方纤锌矿结构。ZnO纳米晶薄膜在可 见光区光透过率 高于90%,光学带宽为3.26eV,仅在 387nm处出现一个很强的近带边(NBE)发射峰。进一步发现ZnO纳米 晶薄膜/p-Si异质结在暗态和365nm紫外光照射下都出现整流特性, 形成了二极管。在暗态下,该二极管的 整流率为3.95(±2.46 V),开启电压约为0.7V,理想因 子为4.65,反偏饱和电流为4.57×10-8 A。在365nm的 紫外光照射下,它的整流率高达24.85(±0.65V),说明它对365nm的紫外光有很高的响应,适合用于紫外光探测 器。 相似文献
263.
采用标准CMOS工艺制备的n~+-p-π-p~+结构的线性APD,其倍增区p层的掺杂分布极大地影响着器件的性能.采用Silvaco仿真软件对倍增区p层进行了设计仿真,研究了p层的注入剂量和注入峰值浓度深度对器件特性的影响.仿真结果表明,设定器件增益为50,在p层的最佳注入剂量为1.82×10~(12)/cm~2,峰值浓度深度为2.1μm左右的最佳工艺条件下,器件的工作电压为73.1 V,过剩噪声因子为4.59,过剩噪声指数在0.34~0.45之间(波长λ=800 nm),优于目前已报道的结果.通过工艺的优化,器件的性能可以得到进一步提高. 相似文献
264.
Ultra-wide tuning single channel filter based on one-dimensional photonic crystal with an air cavity
By inserting an air cavity into a one-dimensional photonic crystal of LiF/GaSb, a tunable filter covering the whole visible range is proposed. Following consideration of the dispersion of the materials, through modulating the thickness of the air cavity, we demonstrate that a single resonant peak can shift from 416.1 to 667.3 nm in the band gap at normal incidence by means of the transfer matrix method. The research also shows that the transmittance of the channel can be maximized when the number of periodic LiF/GaSb layers on one side of the air defect layer is equal to that of the other side. When adding a period to both sides respectively, the full width at half maximum of the defect mode is reduced by one order of magnitude. This structure will provide a promising approach to fabricate practical tunable filters in the visible region with ultra-wide tuning range. 相似文献
265.
Nezhad MR Alimohammadi M Tashkhourian J Razavian SM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(1):199-203
An indirect colorimetric method is presented for detection of trace amounts of hydroquinone (1), catechol (2) and pyrogallol (3). The reduction of AuCl4(-) to Gold nanoparticles (Au-NPs) by these phenolic compounds in the presence of cetyltrimethylammonium chloride (CTAC) produced very intense surface plasmon resonance peak of Au-NPs. The plasmon absorbance of Au-NPs allows the quantitative colorimetric detection of the phenolic compounds. The calibration curves derived from the changes in absorbance at lambda = 568 nm were linear with concentration of hydroquinone, catechol and pyrogallol in the range of 7.0 x 10(-7) to 1.0 x 10(-4)M, 6.0 x 10(-6) to 2.0 x 10(-4)M and 6.0 x 10(-7) to 1.0 x 10(-4)M, respectively. The detection limits were 5.3 x 10(-7), 2.5 x 10(-6) and 3.2 x 10(-7)M for the hydroquinone, catechol and pyrogallol, respectively. The method was applied satisfactorily to the determination of phenolic compounds in water samples and pharmaceutical formulations. 相似文献
266.
An analytical relationship “the current peak height—the potential sweep rate” is derived for the three-dimensional film formation
under ohmic resistance control. The model takes into account both the changing of the coverage degree and the thickening of
the surface film. It is shown that a criterion for definition of the growth type (2D or 3D) of the surface film can be offered.
An offered model is tested for anodic oxidation of silver in sulfuric acid solution. 相似文献
267.
The appearance of unexpected peaks in capillary electrophoresis (CE) is common and can lengthen the time of method development as assay conditions and experimental parameters are varied to understand and mitigate the effects of the additional peaks. Additional peaks can arise when a single-analyte zone is split into multiple zones. Understanding the underlying mechanism of these phenomena, recognizing conditions that favor its presence, and knowing how to confirm and eliminate the effect are important for efficient method optimization. In this study, we examine how the overlap of analyte zones with the sample plug can lead to peak splitting. This is explored experimentally using dual detection CE, which enables both the sample plug and analyte zones to be independently and simultaneously measured from the same detection volume. Simulations performed via COMSOL Multiphysics confirm the origin of the splitting and help guide experiments to reduce and eliminate the effect. Our findings show that this peak splitting mechanism can arise in separations of both small and large molecules but is, especially, prevalent in separations of slowly migrating macromolecules. This effect is also more prevalent when using a short length-to-detector, as is commonly found in microfluidic applications. A simple diffusion-less model is introduced to develop strategies for reducing peak splitting that avoids modifying the apparatus, such as by lengthening the separation length, which can be difficult. Decreasing the sample plug length and slowing the electroosmotic flow can both reduce this effect, which is confirmed experimentally. 相似文献
268.
Ping Li Yuanyuan Ou Zilong Zhang Wenwen Wang Xu Ji Minfeng Fang Qian Li 《Journal of separation science》2023,46(9):2200944
As a famous traditional Chinese formula, Danshen Decoction has the potential to relieve the pain of pulmonary arterial hypertension patients, however, the functional components remain unknown. Herein, we reported a method to screen the functional components in Danshen Decoction targeting endothelin receptor A, an accepted target for the treatment of the disease. The receptor was functionalized on the macroporous silica gel through an epidermal growth factor receptor fusion tag and its covalent inhibitor. Using the affinity gel as the stationary phase, the bioactive compound was identified as salvianolic acid B by mass spectrometry. The binding kinetic parameter (dissociation rate constants kd) of salvianolic acid B with the receptor was determined via peak profiling. Using the specific ligands of the receptor as probes, the binding configuration prediction of salvianolic acid B with the receptor was performed by molecular dynamics simulation. Our results indicated that salvianolic acid B is a potential bioactive compound in Danshen Decoction targeting the receptor. This work showed that receptor chromatography in combination with molecular dynamics simulation is applicable to predicting the binding kinetics and configuration of a ligand to a receptor, providing crucial insight for the rational design of drugs that recognize functional proteins. 相似文献
269.
270.