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951.
952.
SiO2包覆铕(Ⅲ)配合物的荧光纳米粒子合成与性质 总被引:1,自引:0,他引:1
以前驱物pAB-DTPAA-APTEOS、正硅酸乙酯(TEOS)和三氯化铕(EuCl3)等为原料,采用油包水(W/O)的反相微乳液法,在正硅酸乙酯(TEOS)和3-氨丙基三乙氧基硅烷(APTEOS)的共同水解下,制备出新型的SiO2包覆铕配合物荧光纳米粒子Eu-pAB-DTPAA-AP-SiO2。运用TEM、IR、UV-Vis、荧光光谱等技术对荧光纳米粒子进行了表征。TEM结果表明:包覆体呈球形,分散均匀,平均粒径为40nm。纳米粒子与配体、前驱物的紫外吸收谱相比较,峰位发生了一定的红移,表明通过反相微乳液法得到的固体粉末与EuCl3反应后,已经生成配合物Eu-pAB-DTPAA-AP-SiO2。红外光谱研究表明,在801cm-1出现νSi—C的伸缩振动峰,471cm-1处出现νEu—O的伸缩振动峰。由此证实Eu-pAB-DTPAA-AP-SiO2配合物的存在。荧光光谱分析表明,纳米粒子Eu-pAB-DTPAA-AP-SiO2表现出较好的荧光性能,位于592,615,689nm的发射峰分别归属于Eu3 离子的5D0→7F1、5D0→7F2和5D0→7F4跃迁,其中最强峰615nm属于Eu3 的特征跃迁发射。作为一种新型的荧光试剂,该纳米粒子具有粒径小,亲水性强,荧光强度大,且表面的氨基能方便地与生物分子偶联,故可作为优良的时间分辨荧光标记物用于各种高灵敏生物检测技术中。 相似文献
953.
热丝和射频等离子体化学气相沉积法制备定向碳纳米管薄膜 总被引:1,自引:0,他引:1
采用热丝和射频等离子体复合化学气相沉积设备(PE-HF-CVD),以CH4、H2和N2为反应气体.在较低衬底温度下(500℃),用简单的催化剂制备方法--旋涂法在硅片上涂覆Ni(NO3)2溶液,经热处理及H2还原后的Ni颗粒为催化剂,在硅衬底上制备出了垂直于硅片且定向生长的碳纳米管薄膜.扫描电子显微镜(SEM)和透射电子显微镜(TEM)结果显示,1 mol/l的硝酸镍溶液旋涂硅片所得催化剂制得的碳纳米管管径为30~50 nm,长度超过4μm,定向性好.并用拉曼光谱(Raman)对不同摩尔浓度Ni(NO3)2溶液条件下制备的碳纳米管薄膜样品进行了表征. 相似文献
954.
955.
We here outline the importance of open-source, accessible tools for computer-aided drug discovery (CADD). We begin with a discussion of drug discovery in general to provide context for a subsequent discussion of structure-based CADD applied to small-molecule ligand discovery. Next, we identify usability challenges common to many open-source CADD tools. To address these challenges, we propose a browser-based approach to CADD tool deployment in which CADD calculations run in modern web browsers on users’ local computers. The browser app approach eliminates the need for user-initiated download and installation, ensures broad operating system compatibility, enables easy updates, and provides a user-friendly graphical user interface. Unlike server apps—which run calculations “in the cloud” rather than on users’ local computers—browser apps do not require users to upload proprietary information to a third-party (remote) server. They also eliminate the need for the difficult-to-maintain computer infrastructure required to run user-initiated calculations remotely. We conclude by describing some CADD browser apps developed in our lab, which illustrate the utility of this approach. Aside from introducing readers to these specific tools, we are hopeful that this review highlights the need for additional browser-compatible, user-friendly CADD software. 相似文献
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957.
Thi Anh Le Ngoc Quang Tran Yeseul Hong Prof. Hyoyoung Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(4):1037-1043
The exploration of the rational design and synthesis of unique and robust architectured electrodes for the high capacitance, rate capability, and stability of supercapacitors is crucial to the future of energy storage technology. Herein, an in situ synthesis of multilayered titanium carbide MXene tightly caging within a 3 D conducting tangled polypyrrole (PPy) nanowire (NW) network is proposed as an effective strategy to prevent the aggregation of MXene, profoundly enhancing the electrochemical performance of the supercapacitor. Owing to the beneficial effects of an ideal 3 D interconnected porous structure and high electrical conductivity, the obtained electrode exhibits fast charge and ion transport kinetics as well as full usage of active material. As expected, the 3 D Ti3C2Tx@PPY NW exhibits a specific capacitance five times higher than that of pristine MXene (610 F g−1), a good rate capability up to a current density of 25 A g−1, and excellent stability with 100 % retention after 14 000 cycles at 4 A g−1, outperforming the known state-of-the-art MXene-based supercapacitor. Our work provides a facile method for enhancing the performance of MXene-based energy storage devices. 相似文献
958.
Unique block co-polymer P(MAn-St-NIPAm) has been successfully synthesized by reversible addition fragmentation chain transfer radical polymerization protocol. Based on the tunable hydrophobic/hydrophilic properties of the block co-polymer, a new open tubular capillary electrochromatography (OT-CEC) system has been constructed with the prepared block co-polymer as the coating and applied in analysis of β-lactam antibiotics in serum samples. 相似文献
959.
《先进技术聚合物》2018,29(1):226-233
Macroscopic supramolecular assembly plays a key role to bridge the fundamental researches on molecular recognition to the potential applications as supramolecular materials. However, the challenge remains to promote the research from soft hydrogel system to semirigid objects or building blocks. Herein, the concept of flexible spacing coating was employed to modify the model polydimethylsiloxane building blocks, and reversible macroscopic assembly was successfully realized through introducing highly directional, dynamic, and reversible coordinate interactions as driving forces. The driving force for the macroscopic assembly was confirmed by introducing highly competitive ethylene diamine tetra acetic acid solution as an orthodox system to disassemble the assembled blocks. Moreover, the coordinate interaction was further understood through unique in situ measurements of binding forces between building blocks during assembly process. This work of macroscopic supramolecular assembly provides an in situ visible platform, which is significant to clarify the highly fascinating and facile coordinate interactions on the macroscopic assembly behavior. 相似文献
960.