全文获取类型
收费全文 | 164119篇 |
免费 | 38095篇 |
国内免费 | 32511篇 |
专业分类
化学 | 88034篇 |
晶体学 | 1628篇 |
力学 | 8305篇 |
综合类 | 610篇 |
数学 | 15941篇 |
物理学 | 69519篇 |
无线电 | 50688篇 |
出版年
2024年 | 838篇 |
2023年 | 2874篇 |
2022年 | 3287篇 |
2021年 | 3935篇 |
2020年 | 4260篇 |
2019年 | 5399篇 |
2018年 | 4823篇 |
2017年 | 5654篇 |
2016年 | 7070篇 |
2015年 | 8039篇 |
2014年 | 8436篇 |
2013年 | 11181篇 |
2012年 | 12442篇 |
2011年 | 13236篇 |
2010年 | 14596篇 |
2009年 | 14507篇 |
2008年 | 8914篇 |
2007年 | 7843篇 |
2006年 | 7365篇 |
2005年 | 6967篇 |
2004年 | 7098篇 |
2003年 | 6004篇 |
2002年 | 5970篇 |
2001年 | 5648篇 |
2000年 | 4408篇 |
1999年 | 4257篇 |
1998年 | 3581篇 |
1997年 | 3207篇 |
1996年 | 3538篇 |
1995年 | 3686篇 |
1994年 | 3675篇 |
1993年 | 3582篇 |
1992年 | 3184篇 |
1991年 | 2829篇 |
1990年 | 2252篇 |
1989年 | 2287篇 |
1988年 | 2128篇 |
1987年 | 1307篇 |
1986年 | 1395篇 |
1985年 | 1037篇 |
1984年 | 1097篇 |
1982年 | 962篇 |
1981年 | 799篇 |
1980年 | 826篇 |
1979年 | 556篇 |
1978年 | 566篇 |
1977年 | 668篇 |
1976年 | 1075篇 |
1973年 | 473篇 |
1972年 | 554篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Chen Zi-Han Li Yue-Hua Qi Ming-Yu Tang Zi-Rong Xu Yi-Jun 《Research on Chemical Intermediates》2022,48(1):1-12
Research on Chemical Intermediates - Owing to the simultaneous utilization of photogenerated electrons and holes, coupling light-driven hydrogen (H2) evolution reaction (HER) and biomass-derived... 相似文献
2.
3.
Yujie Gao Zhiye Qiu Lei Liu Mengmeng Li Bingjie Xu Dan Yu Dongming Qi Jindan Wu 《Journal of polymer science. Part A, Polymer chemistry》2022,60(15):2191-2212
Refractory wounds have always been an important issue to healthcare systems, whose healing process is always delayed by multiple factors, including bacterial infections, chronic inflammation, and excessive exudates, etc. Employing multifunctional wound dressings is recognized as an effective strategy to deal with refractory wounds, which has yielded promising outcomes in recent years. Among these advanced wound dressings, fibrous dressings have gained growing attention due to their unique merits. Such wound dressings have demonstrated great potential in delivering theranostic agents, such as antibacterial agents, anti-inflammatory drugs, growth factors, and diagnostic probes, etc., for the purposes of accelerating wound healing. This paper reviews the development of multifunctional fibrous dressings and their applications in treating refractory wounds. The construction approaches of novel fibrous dressing with capabilities of antibacterial, anti-inflammation, exudate management and diagnosis were also introduced. Furthermore, the existing problems and challenges are also discussed briefly. 相似文献
4.
Hua Saixiang Zhu Huichao Wang Xiao Wu Mingyuan Wu Qingyun Liu Jiuyi Yang Jianjun Zhang Jianan 《Cellulose (London, England)》2022,29(13):7465-7475
Cellulose - Ultraviolet (UV) protective cotton fabric is a convenient and reliable way to protect human body from sunlight. Herein, a polymerizable UV-absorber,... 相似文献
5.
6.
Jia Dai Xiang Cheng Xiaofeng Li Zhisheng Wang Yufeng Wang Jing Zheng Jun Liu Jiawei Chen Changjin Wu Jinyao Tang 《Advanced functional materials》2021,31(48):2106204
Synthetic active matters are perfect model systems for non-equilibrium thermodynamics and of great potential for novel biomedical and environmental applications. However, most applications are limited by the complicated and low-yield preparation, while a scalable synthesis for highly functional microswimmers is highly desired. In this paper, an all-solution synthesis method is developed where the gold-loaded titania-silica nanotree can be produced as a multi-functional self-propulsion microswimmer. By applying light, heat, and electric field, the Janus nanotree demonstrated multi-mode self-propulsion, including photochemical self-electrophoresis by UV and visible light radiation, thermophoresis by near-infrared light radiation, and induced-charge electrophoresis under AC electric field. Due to the scalable synthesis, the Janus nanotree is further demonstrated as a high-efficiency, low-cost, active adsorbent for water decontamination, where the toxic mercury ions can be reclaimed with enhanced efficiency. 相似文献
7.
Zeng Qing-Wei Wen Zhuo-Yu Fu Jun-Feng Zhou Nan-Run 《International Journal of Theoretical Physics》2021,60(9):3306-3333
International Journal of Theoretical Physics - A new quantum watermark algorithm is presented by combining maximum pixel difference partitioning with the least significant bit substitution... 相似文献
8.
Peng Li Haibin Jiang Ariel Barr Zhichu Ren Rui Gao Hua Wang Weiwei Fan Meifang Zhu Guiyin Xu Ju Li 《Advanced functional materials》2021,31(51):2105845
Mercury, lead, and cadmium are among the most toxic and carcinogenic heavy metal ions (HMIs), posing serious threats to the sustainability of aquatic ecosystems and public health. There is an urgent need to remove these ions from water by a cheap but green process. Traditional methods have insufficient removal efficiency and reusability. Structurally robust, large surface-area adsorbents functionalized with high-selectivity affinity to HMIs are attractive filter materials. Here, an adsorbent prepared by vulcanization of polyacrylonitrile (PAN), a nitrogen-rich polymer, is reported, giving rise to PAN-S nanoparticles with cyclic π-conjugated backbone and electronic conductivity. PAN-S can be coated on ultra-robust melamine (ML) foam by simple dipping and drying. In agreement with hard/soft acid/base theory, N- and S-containing soft Lewis bases have strong binding to Hg2+, Pb2+, Cu2+, and Cd2+, with extraordinary capture efficiency and performance stability. Furthermore, the used filters, when collected and electrochemically biased in a recycling bath, can release the HMIs into the bath and electrodeposit on the counter-electrode as metallic Hg0, Pb0, Cu0, and Cd0, and the PAN-S@ML filter can then be reused at least 6 times as new. The electronically conductive PAN-S@ML filter can be fabricated cheaply and holds promise for scale-up applications. 相似文献
9.
Journal of Signal Processing Systems - With the latest development of automation technology, object detection technology has received more and more research attention. Automated object detection... 相似文献
10.