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941.
942.
Xiangchuan Meng Zhi Xing Xiaotian Hu Zengqi Huang Ting Hu Licheng Tan Fengyu Li Yiwang Chen 《Angewandte Chemie (International ed. in English)》2020,59(38):16602-16608
Perovskite solar cells (PSCs) are a promising photovoltaic technology for stretchable applications because of their flexible, light‐weight, and low‐cost characteristics. However, the fragility of crystals and poor crystallinity of perovskite on stretchable substrates results in performance loss. In fact, grain boundary defects are the “Achilles’ heel” of optoelectronic and mechanical stability. We incorporate a self‐healing polyurethane (s‐PU) with dynamic oxime–carbamate bonds as a scaffold into the perovskite films, which simultaneously enhances crystallinity and passivates the grain boundary of the perovskite films. The stretchable PSCs with s‐PU deliver a stabilized efficiency of 19.15 % with negligible hysteresis, which is comparable to the performance on rigid substrates. The PSCs can maintain over 90 % of their initial efficiency after 3000 hours in air because of their self‐encapsulating structure. Importantly, the self‐healing function of the s‐PU scaffold was verified in situ. The s‐PU can release mechanical stress and repair cracks at the grain boundary on multiple levels. The devices recover 88 % of their original efficiency after 1000 cycles at 20 % stretch. We believe that this ingenious growth strategy for crystalline semiconductors will facilitate development of flexible and stretchable electronics. 相似文献
943.
Jiajia Ru Ting He Binjie Chen Yutong Feng Lianhai Zu Zhijun Wang Qiaobao Zhang Tianzi Hao Ruijin Meng Renchao Che Chi Zhang Jinhu Yang 《Angewandte Chemie (International ed. in English)》2020,59(34):14621-14627
Weak van der Waals interactions between interlayers of two‐dimensional layered materials result in disabled across‐interlayer electron transfer and poor layered structural stability, seriously deteriorating their performance in energy applications. Herein, we propose a novel covalent assembly strategy for MoS2 nanosheets to realize unique MoS2/SnS hollow superassemblies (HSs) by using SnS nanodots as covalent linkages. The covalent assembly based on all‐inorganic and carbon‐free concept enables effective across‐interlayer electron transfer, facilitated ion diffusion kinetics, and outstanding mechanical stability, which are evidenced by experimental characterization, DFT calculations, and mechanical simulations. Consequently, the MoS2/SnS HSs exhibit superb rate performance and long cycling stability in lithium‐ion batteries, representing the best comprehensive performance in carbon‐free MoS2‐based anodes to date. Moreover, the MoS2/SnS HSs also show excellent sodium storage performance in sodium‐ion batteries. 相似文献
944.
Shengbo Zhang Meng Jin Tongfei Shi Miaomiao Han Qiao Sun Yue Lin Zhenhua Ding Li Rong Zheng Guozhong Wang Yunxia Zhang Haimin Zhang Huijun Zhao 《Angewandte Chemie (International ed. in English)》2020,59(32):13423-13429
Single‐atom catalysts have demonstrated their superiority over other types of catalysts for various reactions. However, the reported nitrogen reduction reaction single‐atom electrocatalysts for the nitrogen reduction reaction exclusively utilize metal–nitrogen or metal–carbon coordination configurations as catalytic active sites. Here, we report a Fe single‐atom electrocatalyst supported on low‐cost, nitrogen‐free lignocellulose‐derived carbon. The extended X‐ray absorption fine structure spectra confirm that Fe atoms are anchored to the support via the Fe‐(O‐C2)4 coordination configuration. Density functional theory calculations identify Fe‐(O‐C2)4 as the active site for the nitrogen reduction reaction. An electrode consisting of the electrocatalyst loaded on carbon cloth can afford a NH3 yield rate and faradaic efficiency of 32.1 μg h?1 mgcat.?1 (5350 μg h?1 mgFe?1) and 29.3 %, respectively. An exceptional NH3 yield rate of 307.7 μg h?1 mgcat.?1 (51 283 μg h?1 mgFe?1) with a near record faradaic efficiency of 51.0 % can be achieved with the electrocatalyst immobilized on a glassy carbon electrode. 相似文献
945.
Jinyi Dong Meng Wang Yihao Zhou Chao Zhou Qiangbin Wang 《Angewandte Chemie (International ed. in English)》2020,59(35):15038-15042
Self‐assembled plasmonic logic gates that read DNA molecules as input and return plasmonic chiroptical signals as outputs are reported. Such logic gates are achieved on a DNA‐based platform that logically regulate the conformation of a chiral plasmonic nanostructure, upon specific input DNA strands and internal computing units. With systematical designs, a complete set of Boolean logical gates are realized. Intriguingly, the logic gates could be endowed with adaptiveness, so they can autonomously alter their logics when the environment changes. As a demonstration, a logic gate that performs AND function at body temperature while OR function at cold storage temperature is constructed. In addition, the plasmonic chiroptical output has three distinctive states, which makes a three‐state molecular logic gate readily achievable on this platform. Such DNA‐based plasmonic logic gates are envisioned to execute more complex tasks giving these unique characteristics. 相似文献
946.
Hai‐Dong Xia Zhong‐Liang Li Qiang‐Shuai Gu Xiao‐Yang Dong Jia‐Heng Fang Xuan‐Yi Du Li‐Lei Wang Xin‐Yuan Liu 《Angewandte Chemie (International ed. in English)》2020,59(39):16926-16932
We describe a photoinduced copper‐catalyzed asymmetric radical decarboxylative alkynylation of bench‐stable N‐hydroxyphthalimide(NHP)‐type esters of racemic alkyl carboxylic acids with terminal alkynes, which provides a flexible platform for the construction of chiral C(sp3)?C(sp) bonds. Critical to the success of this process are not only the use of the copper catalyst as a dual photo‐ and cross‐coupling catalyst but also tuning of the NHP‐type esters to inhibit the facile homodimerization of the alkyl radical and terminal alkyne, respectively. Owing to the use of stable and easily available NHP‐type esters, the reaction features a broader substrate scope compared with reactions using the alkyl halide counterparts, covering (hetero)benzyl‐, allyl‐, and aminocarbonyl‐substituted carboxylic acid derivatives, and (hetero)aryl and alkyl as well as silyl alkynes, thus providing a vital complementary approach to the previously reported method. 相似文献
947.
Hai‐Long Qian Fan‐Lin Meng Cheng‐Xiong Yang Xiu‐Ping Yan 《Angewandte Chemie (International ed. in English)》2020,59(40):17607-17613
Design of stable adsorbents for selective gold recovery with large capacity and fast adsorption kinetics is of great challenge, but significant for the economy and the environment. Herein, we show the design and preparation of an irreversible amide‐linked covalent organic framework (COF) JNU‐1 via a building block exchange strategy for efficient recovery of gold. JNU‐1 was synthesized through the exchange of 4,4′‐biphenyldicarboxaldehyde (BA) in mother COF TzBA consisting of 4,4′,4′′‐(1,3,5‐triazine‐2,4,6‐triyl)trianiline (Tz) and BA with terephthaloyl chloride. The irreversible amide linked JNU‐1 gave good stability, unprecedented fast kinetics, excellent selectivity and outstanding adsorption capacity for gold recovery. X‐ray photoelectron spectroscopy along with thermodynamic study and quantum mechanics calculation reveals that the excellent performance of JNU‐1 for gold recovery results from the formation of hydrogen bonds C(N)?H???Cl and coordinate interaction of O and Au. The rational design of irreversible bonds as both inherent linkage and functional groups in COFs is a promising way to prepare stable COFs for diverse applications. 相似文献
948.
Meng Su Feifei Qin Zeying Zhang Bingda Chen Qi Pan Zhandong Huang Zheren Cai Zhipeng Zhao Xiaotian Hu Dominique Derome Jan Carmeliet Yanlin Song 《Angewandte Chemie (International ed. in English)》2020,59(34):14234-14240
A key issue of micro/nano devices is how to integrate micro/nanostructures with specified chemical components onto various curved surfaces. Hydrodynamic printing of micro/nanostructures on three‐dimensional curved surfaces is achieved with a strategy that combines template‐induced hydrodynamic printing and self‐assembly of nanoparticles (NPs). Non‐lithography flexible wall‐shaped templates are replicated with microscale features by dicing a trench‐shaped silicon wafer. Arising from the capillary pumped function between the template and curved substrates, NPs in the colloidal suspension self‐assemble into close‐packed micro/nanostructures without a gravity effect. Theoretical analysis with the lattice Boltzmann model reveals the fundamental principles of the hydrodynamic assembly process. Spiral linear structures achieved by two kinds of fluorescent NPs show non‐interfering photoluminescence properties, while the waveguide and photoluminescence are confirmed in 3D curved space. The printed multiconstituent micro/nanostructures with single‐NP resolution may serve as a general platform for optoelectronics beyond flat surfaces. 相似文献
949.
Fei Lu Ding Yi Shoujie Liu Fei Zhan Bo Zhou Lin Gu Dmitri Golberg Xi Wang Jiannian Yao 《Angewandte Chemie (International ed. in English)》2020,59(40):17712-17718
A dual‐site catalyst allows for a synergetic reaction in the close proximity to enhance catalysis. It is highly desirable to create dual‐site interfaces in single‐atom system to maximize the effect. Herein, we report a cation‐deficient electrostatic anchorage route to fabricate an atomically dispersed platinum–titania catalyst (Pt1O1/Ti1?xO2), which shows greatly enhanced hydrogen evolution activity, surpassing that of the commercial Pt/C catalyst in mass by a factor of 53.2. Operando techniques and density functional calculations reveal that Pt1O1/Ti1?xO2 experiences a Pt?O dual‐site catalytic pathway, where the inherent charge transfer within the dual sites encourages the jointly coupling protons and plays the key role during the Volmer–Tafel process. There is almost no decay in the activity of Pt1O1/Ti1?xO2 over 300 000 cycles, meaning 30 times of enhancement in stability compared to the commercial Pt/C catalysts (10 000 cycles). 相似文献
950.
XuanLin Meng Yang Li Chongchong Lu Man Zhao Ming Li ShaoLi Wang ChangBao Zhao Bao Lin LuYue Shang Zhaohui Chu Xinhua Ding 《Journal of separation science》2020,43(12):2311-2320
In a recent study, anthocyanins, which have a strong free radical‐scavenging activity, were examined for their potential to effectively prevent cancer. However, clinical trials are limited by the purity of the anthocyanin. Multiple methods are used to extract and purify anthocyanins. Based on previous work on Solanum nigrum, which is a widely distributed plant, in this study, DM130 macroporous resin, Sephadex LH20, and a C18 column were used to separate cis–trans anthocyanin isomers. These anthocyanins constitute the majority of total S. nigrum anthocyanins. The results showed that this “DM130‐LH20‐C18 system” can be used to obtain a cinnamic acid‐derived cis–trans anthocyanin, petunidin‐3‐(p‐coumaroyl)‐rutinoside‐5‐glucoside, with a purity of 98.5%, for effective quantitation. In order to determine the antioxidant ability of the petunidin‐3‐(p‐coumaroyl)‐rutinoside‐5‐glucoside cis–trans isomers, three ordinary methods were adopted. The maximum antioxidant ability of the cis–trans anthocyanin was dozens of times higher than that of vitamin C. 相似文献