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991.
Shu Yao Minati Malide Samuel Ngaujah Li Li Zhao Li Liping Sun Zhen Huang Lin Xie Ran Chu Chengcheng Li Beihua Kong Kun Song 《Journal of the Iranian Chemical Society》2018,15(8):1733-1739
The traditional treatment has inevitable drawbacks of nonspecific lymph targeting, poor therapeutic efficiency and residual metastatic for advanced cancer patients with lymph node metastases. To overcome these shortcomings, we prepare a nano-carrier drug delivery system. Photosensitizer hematoporphyrin monomethyl ether (HMME)-loaded poly (n-butylcyanoacrylate) nanoparticles (PBCA-NPs) was prepared successfully. The particle size was approximately 160 nm, the envelopment rate was 87.9%, and the drug loading rate was about 13.4%. The drug release study in vitro showed that the cumulative release rates of HMME-PBCA-NPs group was much less than free HMME group. The drug distribution in different tissues showed that the peak-reach time was 3 h in free HMME group and 6 h in nanoparticles group. All of these results confirmed the slow release characteristic of nanoparticles. In lymph node tissues, the HMME concentrations in HMME-PBCA-NPs group were much higher than those of the free HMME group at any time points we tested, in which the maximum difference concentration of HMME appeared at 6 h (1.2884?±?0.04695 vs. 0.0438?±?0.00558 µg/mg) after drug delivery. The mesenteric lymph nodes of rabbits were enlarged obviously in the NP group than in free HMME group at 6 h after drug delivery. All of these results confirmed the slow release characteristic and the lymphatic targeting characteristic of nanoparticles. In summary, we developed a lymphatic targeting nanoparticles drug delivery system successfully, which showed perfect lymph targeting and has the potential to be a new therapy strategy for advanced cancer patients with lymph node metastasis. 相似文献
992.
Maximizing the Number of Interfacial Sites in Single‐Atom Catalysts for the Highly Selective,Solvent‐Free Oxidation of Primary Alcohols
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Tianbo Li Dr. Fei Liu Yan Tang Dr. Lin Li Prof. Shu Miao Yang Su Dr. Junying Zhang Prof. Jiahui Huang Hui Sun Prof. Masatake Haruta Prof. Aiqin Wang Prof. Botao Qiao Prof. Jun Li Prof. Tao Zhang 《Angewandte Chemie (International ed. in English)》2018,57(26):7795-7799
The solvent‐free selective oxidation of alcohols to aldehydes with molecular oxygen is highly attractive yet challenging. Interfacial sites between a metal and an oxide support are crucial in determining the activity and selectivity of such heterogeneous catalysts. Herein, we demonstrate that the use of supported single‐atom catalysts (SACs) leads to high activity and selectivity in this reaction. The significantly increased number of interfacial sites, resulting from the presence of individually dispersed metal atoms on the support, renders SACs one or two orders of magnitude more active than the corresponding nanoparticle (NP) catalysts. Lattice oxygen atoms activated at interfacial sites were found to be more selective than O2 activated on metal NPs in oxidizing the alcohol substrate. This work demonstrates for the first time that the number of interfacial sites is maximized in SACs, providing a new avenue for improving catalytic performance by developing appropriate SACs for alcohol oxidation and other reactions occurring at metal–support interfacial sites. 相似文献
993.
From Metal–Organic Frameworks to Single‐Atom Fe Implanted N‐doped Porous Carbons: Efficient Oxygen Reduction in Both Alkaline and Acidic Media
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Long Jiao Gang Wan Rui Zhang Dr. Hua Zhou Prof. Dr. Shu‐Hong Yu Prof. Dr. Hai‐Long Jiang 《Angewandte Chemie (International ed. in English)》2018,57(28):8525-8529
It remains highly desired but a great challenge to achieve atomically dispersed metals in high loadings for efficient catalysis. Now porphyrinic metal–organic frameworks (MOFs) have been synthesized based on a novel mixed‐ligand strategy to afford high‐content (1.76 wt %) single‐atom (SA) iron‐implanted N‐doped porous carbon (FeSA‐N‐C) via pyrolysis. Thanks to the single‐atom Fe sites, hierarchical pores, oriented mesochannels and high conductivity, the optimized FeSA‐N‐C exhibits excellent oxygen reduction activity and stability, surpassing almost all non‐noble‐metal catalysts and state‐of‐the‐art Pt/C, in both alkaline and more challenging acidic media. More far‐reaching, this MOF‐based mixed‐ligand strategy opens a novel avenue to the precise fabrication of efficient single‐atom catalysts. 相似文献
994.
995.
Real‐Time Probing of Nanowire Assembly Kinetics at the Air–Water Interface by In Situ Synchrotron X‐Ray Scattering
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Zhen He Dr. Hui‐Jun Jiang Long‐Long Wu Dr. Jian‐Wei Liu Dr. Geng Wang Xiao Wang Dr. Jin‐Long Wang Prof. Zhong‐Huai Hou Prof. Gang Chen Prof. Shu‐Hong Yu 《Angewandte Chemie (International ed. in English)》2018,57(27):8130-8134
Although many assembly strategies have been used to successfully construct well‐aligned nanowire (NW) assemblies, the understanding of their assembly kinetics has remained elusive, which restricts the development of NW‐based device and circuit fabrication. Now a versatile strategy that combines interfacial assembly and synchrotron‐based grazing‐incidence small‐angle X‐ray scattering (GISAXS) is presented to track the assembly evolution of the NWs in real time. During the interface assembly process, the randomly dispersed NWs gradually aggregate to form small ordered NW‐blocks and finally are constructed into well‐defined NW monolayer driven by the conformation entropy. The NW assembly mechanism can be well revealed by the thermodynamic analysis and large‐scale molecular dynamics theoretical evaluation. These findings point to new opportunities for understanding NW assembly kinetics and manipulating NW assembled structures by bottom‐up strategy. 相似文献
996.
Yong Li Yingzheng Shu Muwen Liang Dr. Xilei Xie Dr. Xiaoyun Jiao Prof. Xu Wang Prof. Bo Tang 《Angewandte Chemie (International ed. in English)》2018,57(38):12415-12419
Carbon monoxide (CO) is proposed as an active pharmaceutical agent with promising pharmaceutical prospects, as it has been involved in multifaceted modulation of diverse physiological and pathological processes. However, questions remain for therapeutic application of inhaled CO attributed to the inherent great affinity between CO and hemoglobin. Therefore, a robust platform with the function of CO transport and controllable release, depending on the local status of an organism, is of prominent significance for effectively avoiding the side effects of CO inhalation and optimizing the biological regulation function of CO. Utilizing the oxidative stress biomarker H2O2 as a trigger and combining with photo‐control, a two‐photon H2O2‐activated CO photoreleaser, FB, featuring highly sensitive and specific H2O2 sensing and photocontrollable CO release, was developed and the vasodilation effect of CO against angiotensin II was demonstrated. 相似文献
997.
Conjugated Polymer Nanoparticles with Appended Photo‐Responsive Units for Controlled Drug Delivery,Release, and Imaging
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Dr. Thangaraj Senthilkumar Lingyun Zhou Prof. Qi Gu Dr. Libing Liu Dr. Fengting Lv Prof. Shu Wang 《Angewandte Chemie (International ed. in English)》2018,57(40):13114-13119
Carriers that can afford tunable physical and structural changes are envisioned to address critical issues in controlled drug delivery applications. Herein, photo‐responsive conjugated polymer nanoparticles (CPNs) functionalized with donor–acceptor Stenhouse adduct (DASA) and folic acid units for controlled drug delivery and imaging are reported. Upon visible‐light (λ=550 nm) irradiation, CPNs simultaneously undergo structure, color, and polarity changes that release encapsulated drugs into the cells. The backbone of CPNs favors FRET to DASA units boosting their fluorescence. Notably, drug‐loaded CPNs exhibit excellent biocompatibility in the dark, indicating perfect control of the light trigger over drug release. Delivery of both hydrophilic and hydrophobic drugs with good loading efficiency was demonstrated. This strategy enables remotely controlled drug delivery with visible‐light irradiation, which sets an example for designing delivery vehicles for non‐invasive therapeutics. 相似文献
998.
Nanami Hara Shu Fujisawa Mizuki Fujita Mikako Miyazawa Kazuma Ochiai Satoshi Katsuda Tetsuya Fujimoto 《Tetrahedron》2018,74(2):296-302
Kinetic resolution of secondary alcohols by benzoylation using a phosphinite derivative of (1S,2R)-1-amino-2-indanol as the catalyst was investigated. The aminophosphinite catalyst is effective for the kinetic resolution of aryl cycloalkyl carbinols with a small number of examples for organocatalytic kinetic resolution to achieve resolution with s = up to 44. Although the benzoylation of phenylalkanols proceeded with a low selectivity, 1-arylalkanols bearing at least one substituent at the ortho position on the benzene ring or a branched alkyl group on the carbinol carbon were resolved with acceptable selectivity. 相似文献
999.
Dr. Shu‐Xian Hu M. Sc. Wan‐Lu Li M. Sc. Jun‐Bo Lu Dr. Junwei Lucas Bao Dr. Haoyu S. Yu Prof. Dr. Donald G. Truhlar Dr. John K. Gibson Dr. Joaquim Marçalo Prof. Dr. Mingfei Zhou Prof. Dr. Sebastian Riedel Prof. Dr. W. H. Eugen Schwarz Prof. Dr. Jun Li 《Angewandte Chemie (International ed. in English)》2018,57(12):3242-3245
The concept of oxidation state ( OS ) is based on the concept of Lewis electron pairs, in which the bonding electrons are assigned to the more electronegative element. This approach is useful for keeping track of the electrons, predicting chemical trends, and guiding syntheses. Experimental and quantum‐chemical results reveal a limit near +8 for the highest OS in stable neutral chemical substances under ambient conditions. OS =+9 was observed for the isolated [IrO4]+ cation in vacuum. The prediction of OS =+10 for isolated [PtO4]2+ cations is confirmed computationally for low temperatures only, but hasn't yet been experimentally verified. For high OS species, oxidation of the ligands, for example, of O?2 with formation of .O?1 and O?O bonds, and partial reduction of the metal center may be favorable, possibly leading to non‐Lewis type structures. 相似文献
1000.
Thioketone‐Directed Palladium(II)‐Catalyzed C−H Arylation of Ferrocenes with Aryl Boronic Acids
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Zhong‐Jian Cai Chen‐Xu Liu Dr. Qing Gu Prof. Dr. Shu‐Li You 《Angewandte Chemie (International ed. in English)》2018,57(5):1296-1299
A palladium(II)‐catalyzed thioketone‐chelation‐assisted direct C?H arylation of ferrocenes is described. With thioketone as an efficient directing group, various monoaryl‐ and diaryl‐substituted thiocarbonylferrocenes were obtained by palladium‐catalyzed direct C?H functionalization in high yields under mild and base‐free reaction conditions. Furthermore, the arylated thiocarbonylferrocene could undergo diverse transformations. 相似文献