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71.
Boosting Hydrogen Peroxide Electrosynthesis via Modulating the Interfacial Hydrogen-Bond Environment
Yushuang Fang Yu Fan Kunchi Xie Wangxin Ge Yihua Zhu Zhiwen Qi Zhen Song Hongliang Jiang Chunzhong Li 《Angewandte Chemie (International ed. in English)》2023,62(27):e202304413
Designing highly efficient and stable electrode-electrolyte interface for hydrogen peroxide (H2O2) electrosynthesis remains challenging. Inhibiting the competitive side reaction, 4 e− oxygen reduction to H2O, is essential for highly selective H2O2 electrosynthesis. Instead of hindering excessive hydrogenation of H2O2 via catalyst modification, we discover that adding a hydrogen-bond acceptor, dimethyl sulfoxide (DMSO), to the KOH electrolyte enables simultaneous improvement of the selectivity and activity of H2O2 electrosynthesis. Spectral characterization and molecular simulation confirm that the formation of hydrogen bonds between DMSO and water molecules at the electrode-electrolyte interface can reduce the activity of water dissociation into active H* species. The suitable H* supply environment hinders excessive hydrogenation of the oxygen reduction reaction (ORR), thus improving the selectivity of 2 e− ORR and achieving over 90 % selectivity of H2O2. This work highlights the importance of regulating the interfacial hydrogen-bond environment by organic molecules as a means of boosting electrochemical performance in aqueous electrosynthesis and beyond. 相似文献
72.
A new type of sulfoxide, 4-(2-(2-(methylsulfinyl) ethyl)-4-nitrophenyl)- morpholine (I), was designed and prepared in good yield. Upon the combination of I and bis(trichloromethyl)carbonate, the Swern oxidation of primary and secondary alcohols was significantly promoted under mild conditions, which afforded the corresponding aldehydes or ketones in good yields. It is noteworthy that the reoxidation of the isolated by-product sulfide V could be further recycled in Swern oxidation. 相似文献
73.
Inside Cover: Pt3Co Octapods as Superior Catalysts of CO2 Hydrogenation (Angew. Chem. Int. Ed. 33/2016)
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74.
Chao Zhang Hongliang Kang Pingping Li Zhijing Liu Yijin Zhang Ruigang Liu Jun-feng Xiang Yong Huang 《Cellulose (London, England)》2016,23(2):1165-1175
Polar aprotic solvents are considered to act as cosolvents with ionic liquids (ILs) for cellulose, strengthening the solvating ability of ILs by improving their cellulose solvating kinetics without influencing the solubility of cellulose in ILs. In this work, it was found that dimethylsulfoxide (DMSO) at low concentration improves the cellulose solvating ability of [AMIM][Cl], but weakens it at high concentration. To clarify the mechanism of these dual effects of DMSO on the cellulose solvating ability of [AMIM][Cl], the [AMIM][Cl]/DMSO system was investigated using excess infrared spectroscopy, nuclear magnetic resonance (NMR) T 2 relaxometry, 1H NMR, 35Cl NMR, and dynamic light scattering. The results indicate that the tight association between the cation and anion in the [AMIM][Cl] network is loosened at low DMSO concentration. As a result, mass transport is accelerated due to the enhanced dynamics of [AMIM][Cl], promoting the cellulose solvating kinetics of [AMIM][Cl]. However, ion clusters of [AMIM][Cl] start to form when the molar fraction of DMSO (x DMSO) exceeds 0.5. The hydrogen bonds between cations and anions in the ion clusters become much stronger than in pure [AMIM][Cl], leading to decreased ability of [AMIM][Cl] to form hydrogen bonds with cellulose and thus decreased cellulose solubility in the [AMIM][Cl]/DMSO mixture. 相似文献
75.
Fei?Lu Chao?Zhang Hongliang?Kang Yong?HuangEmail author Ruigang?LiuEmail author 《Cellulose (London, England)》2016,23(5):2877-2885
The extensional flow behaviors of cellulose/NaOH/urea/H2O solution were investigated by using capillary breakup extensional rheometry (CaBER). The effects of temperature, storage time and cellulose concentrations on both the storage modulus G′ and the loss modulus G″ were also analyzed. For 2 wt% cellulose solution, the G′, G″ and filament lifetime remained unchanged after long storage time. While, for 4 wt% cellulose solution, physical gels could form at either higher temperature or for longer storage time, and the filament lifetime, the relaxation time (λ e ) and the initial extensional viscosity (η e0) first increased and then decreased with increase of the storage time. The transition points of the filament lifetime shifted to lower storage time with the increase of the temperature. The η e0 is proportional to λ e . The results presented suggest that the extensional properties of the cellulose/NaOH/urea/H2O solution first increase and then decrease during the gelation process, and the spinning time, which decreases linearly with the increase in the storage temperature, must be controlled below the time that η e0 starts to decrease. 相似文献
76.
Xiaozhuang Wang Yuekun Heng Zhi Wu Cheng Li Yongjie Sun Hongliang Dai Shengsen Sun Rongxing Yang Zhen Liu Ping Cao Jie Zhang Yun Wang Weijia Sun Siyu Wang Xiaolu Ji Jinzhou Zhao Wenxuan Gong Mei Ye Xiaoyan Ma Mingming Chen Meihang Xu Xiaolan Luo Kejun Zhu Zhenan Liu Xiaoshan Jiang 《The European Physical Journal C - Particles and Fields》2016,76(4):211
77.
当前在高速数据系统中,LVDS接口已被广泛应用,为实现同系列设备之间的智能识别、自动握手以及LVDS高速数据链路通信质量的检测,利用FPGA的IO电路结构,设计一种模拟IIC总线协议电路,该IIC总线高效地实现设备之间的信息双向传递;同时利用FPGA内部丰富寄存器资源设计PRBS码型电路来检测LVDS接口芯片电路误码率。实际测试表明该多通道LVDS传输方式在2米长电缆连接能够实现数据的稳定、低误码率传输,并且在时钟频率为100MHz时,数据传输速率高达4.68Gb/s。 相似文献
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80.
二溴羟基苯基荧光酮荧光熄灭法测定铜 总被引:3,自引:0,他引:3
研究了在pH 6 2~ 8 2磷酸二氢钾 磷酸氢二钠缓冲体系中 ,非离子表面活性剂TritonX 10 0存在下 ,铜 (Ⅱ )与二溴羟基苯基荧光酮 (DBH PF)形成 1∶2红色三元混配合物而使荧光熄灭 ,建立了荧光熄灭法测定铜的新方法。配合物的λex=5 3 0nm ,λem=5 60nm ,含量在 0~ 80 μg·L-1范围内有良好的线性关系 ,检测限为 0 2 μg·L-1。体系的灵敏度高 ,选择性好。Al(Ⅲ )、Fe(Ⅲ )、Ti(Ⅳ )的干扰 ,可用氟化钠、苦杏仁酸掩蔽。方法快速简便 ,用于人发、茶叶及水中微量铜的测定与AAS相符 ,RSD(n=5 ) <6 9% ,回收率在 98%~ 10 4 %之间。 相似文献