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941.
具有β-(1→6)-半乳吡喃糖骨架和α-L-(1→3)-阿拉伯呋喃糖侧链的阿拉伯半乳寡糖的简易合成 总被引:1,自引:0,他引:1
4-Methoxyphenyl glycoside of β-D-Galp-(1→6)-[α-L-Araf-(1→3)-]β-D-Galp-(1→6)-β-D-Galp-(1→6)-{β-D-Galp-(1→6)-[α-L-Araf-(1→3)-]β-D-Galp-(1→6)-β-D-Galp-(1→6)-}2β-D-Galp-(1→6)-[α-L-Araf-(1→)3)-]β-D-Galp-(1→)6)-β-D-Galp was synthesized with 2,3,4,6-tetra-O-benzoyl-α-D-galactopyranosyl trichloroacetimidate (1), 6-O-acetyl-2,3,4-tri-O-benzoyl-α-D-galactopyranosyl trichloroacetimidate (11), 4-methoxyphenyl 3-O-allyl-2,4-tri-O-benzoyl-β-D-galactopyranoside (2),isopropyl 3-O-allyl-2,4-tri-O-benzoyl--thio-β-D-galactopyranoside (12),4-methoxyphenyl 2,3,4-tri-O-benzoyl-β-D-galactopyranoside (5), and 2,3,5-tri-O-benzoyl-α-L-arabinofuranosyl trichloroacetimidate (8) as the key synthons. 相似文献
942.
Five new copper(I)/silver(I) complexes containing 2-aminopyridine, [Cu(μ-Cl)(2-Apy)(PPh3)]2(1), [Ag(μ-Cl)(2-Apy)(PPh3)]2(2), [Ag(μ-Br)(2-Apy)PPh3)]2(3), [Ag(μ-ONO2)(2-Apy)(PPh3)]2(4), [Ag(μ-ONO2)(2-Apy)(AsPh3)]2(5) have been synthesised for the first time. Complexes 1–5 are obtained by the reactions of MX (MX = CuCl for 1; M = Ag for 2–5; X = Cl, Br for 2–3; X = NO3 for 4–5) with the monodentate ligands EPh3 (E = P for 1–4; E = As for 5) and 2-Apy in the molar ratio of 1:1:2 in the mixed solvent of CH2Cl2 and MeOH. Complexes 1–5 are characterised by IR and X-ray diffraction. In 1–5, chloride, bromide and nitrate ions bridge two metal atoms to form dinuclear complexes containing the parallelogram cores M2X2 (M = Cu, Ag). 相似文献
943.
Changmei Jiao Tong Meng Honghong Lu Yuxiang Zuo Xiaoke Zhi Guangchuan Liang 《Journal of Solid State Electrochemistry》2017,21(2):495-501
In order to avoid the shortcomings of large particle size and poor uniformity of material synthesized by the traditional solid-state method, this paper utilizes a simple improvement of calcination process (i.e., calcination–milling–recalcination) based on the traditional solid-state synthesis to successfully prepare a large number of well-distributed, micrometer-sized, spherical secondary LiNi0.5Mn1.5O4 particles. Each particle is composed of nano- and/or sub-micrometer-sized grains. Results of the electrochemical performance tests show that the material exhibits a remarkable cycle performance and rate capability compared with that obtained from traditional synthesis method; the spherical LiNi0.5Mn1.5O4 particles can deliver a large capacity of 135.8 mAh g?1 at a 1 C discharge rate with a high retention of 77 % after 741 cycles and a good capacity of 105.9 mAh g?1 at 10 C. Cyclic voltammetry measurements confirm that the significantly improved electrochemical properties are due to enhanced electronic conductivity and lithium-ion diffusion coefficient resulting from the optimized morphology and particle size. This improved method is more suitable for mass production. 相似文献
944.
Wen‐Zuo Li Jian‐Bo Cheng Qing‐Zhong Li Bao‐An Gong Jia‐Zhong Sun 《International journal of quantum chemistry》2010,110(14):2683-2688
Geometries, frequencies, and energies of the 12B1, 12A2, 12B2, 22B1, 22B2, and 12A1, of the C6H5Br+ ion were calculated by using CASSCF and CASPT2 methods in conjunction with an ANO‐RCC basis. The CASPT2//CASSCF adiabatic excitation energies and CASPT2 relative energies for the six states are in good agreement with experiment. The X, A, B, C, and D electronic states of the C6H5Br+ ion were assigned to be X2B1, A2A2, B2B2, C2B1, and D2B2 based on the CASSCF and CASPT2 calculations. The assignment on the D state of the C6H5Br+ ion is different from the previously published works. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
945.
946.
Yang Shi Jing Wan Gui‐Xian Liu Tong‐Tong Zuo Yue‐Xian Song Bing Liu Yu‐Guo Guo Rui Wen Li‐Jun Wan 《Angewandte Chemie (International ed. in English)》2020,59(41):18120-18125
Unstable electrode/solid‐state electrolyte interfaces and internal lithium dendrite penetration hamper the applications of solid‐state lithium‐metal batteries (SSLMBs), and the underlying mechanisms are not well understood. Herein, in situ optical microscopy provides insights into the lithium plating/stripping processes in a gel polymer electrolyte and reveals its dynamic evolution. Spherical lithium deposits evolve into moss‐like and branch‐shaped lithium dendrites with increasing current densities. Remarkably, the on‐site‐formed solid electrolyte interphase (SEI) shell on the lithium dendrite is distinctly captured after lithium stripping. Inducing an on‐site‐formed SEI shell with an enhanced modulus to wrap the lithium precipitation densely and uniformly can regulate dendrite‐free behaviors. An in‐depth understanding of lithium dendrite evolution and its functional SEI shell will aid in the optimization of SSLMBs. 相似文献
947.
脂性油膏药物中黄芩甙含量的高效液相色谱分析 总被引:1,自引:0,他引:1
用0.02mol/L的三羟甲基胺基甲烷(用磷酸调pH值至7)和甲醇(含2%乙酸和0.25%庚烷磺酸钠)作流动相进行梯度洗脱,建立了脂性油膏药物中黄苓甙含量的反相高效液相色谱分析方法,本法分析速度快、重现性好,黄苓甙的平均回收率为103.7%. 相似文献
948.
Hao Zhang Prof. Wanchun Xiang Xuejiao Zuo Xiaojing Gu Shiang Zhang Yachao Du Zhiteng Wang Yali Liu Haifeng Wu Peijun Wang Qingyue Cui Hang Su Prof. Qingwen Tian Prof. Shengzhong Liu 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216634
Minimizing surface defect is vital to further improve power conversion efficiency (PCE) and stability of inorganic perovskite solar cells (PSCs). Herein, we designed a passivator trifluoroacetamidine (TFA) to suppress CsPbI3−xBrx film defects. The amidine group of TFA can strongly chelate onto the perovskite surface to suppress the iodide vacancy, strengthened by additional hydrogen bonds. Moreover, three fluorine atoms allow strong intermolecular connection via intermolecular hydrogen bonds, thus constructing a robust shield against moisture. The TFA-treated PSCs exhibit remarkably suppressed recombination, yielding the record PCEs of 21.35 % and 17.21 % for 0.09 cm2 and 1.0 cm2 device areas, both of which are the highest for all-inorganic PSCs so far. The device also achieves a PCE of 39.78 % under indoor illumination, the highest for all-inorganic indoor photovoltaic devices. Furthermore, TFA greatly improves device ambient stability by preserving 93 % of the initial PCE after 960 h. 相似文献
949.
Xiang-Ji Liao Dongdong Pu Li Yuan Jingjing Tong Shuai Xing Dr. Zhen-Long Tu Prof. Jing-Lin Zuo Prof. Wen-Hua Zheng Prof. You-Xuan Zheng 《Angewandte Chemie (International ed. in English)》2023,62(6):e202217045
Chiral boron/nitrogen doped multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters are promising for highly efficient and color-pure circularly polarized organic light-emitting diodes (CP-OLEDs). Herein, we report two pairs of MR-TADF materials (Czp-tBuCzB, Czp-POAB) based on planar chiral paracyclophane with photoluminescence quantum yields of up to 98 %. The enantiomers showed symmetric circularly polarized photoluminescence spectra with dissymmetry factors |gPL| of up to 1.6×10−3 in doped films. Meanwhile, the sky-blue CP-OLEDs with (R/S)-Czp-tBuCzB showed an external quantum efficiency of 32.1 % with the narrowest full-width at half-maximum of 24 nm among the reported CP-OLEDs, while the devices with (R/S)-Czp-POAB displayed the first nearly pure green CP electroluminescence with |gEL| factors at the 10−3 level. These results demonstrate the incorporation of planar chirality into MR-TADF emitter is a reliable strategy for constructing of efficient CP-OLEDs. 相似文献
950.
Dr. Guixiang Li Dr. Yalei Hu Prof. Dr. Meng Li Ying Tang Zuhong Zhang Dr. Artem Musiienko Qing Cao Fatima Akhundova Jinzhao Li Karunanantharajah Prashanthan Dr. Fengjiu Yang Patryk Janasik Augustine N. S. Appiah Sergei Trofimov Nikolaos Livakas Shengnan Zuo Luyan Wu Luyao Wang Dr. Yuqian Yang Dr. Benjamin Agyei-Tuffour Dr. Rowan W. MacQueen Dr. Boris Naydenov Dr. Thomas Unold Prof. Dr. Eva Unger Dr. Ece Aktas Prof. Dr. Siegfried Eigler Prof. Dr. Antonio Abate 《Angewandte Chemie (International ed. in English)》2023,62(39):e202307395
Stability issues could prevent lead halide perovskite solar cells (PSCs) from commercialization despite it having a comparable power conversion efficiency (PCE) to silicon solar cells. Overcoming drawbacks affecting their long-term stability is gaining incremental importance. Excess lead iodide (PbI2) causes perovskite degradation, although it aids in crystal growth and defect passivation. Herein, we synthesized functionalized oxo-graphene nanosheets (Dec-oxoG NSs) to effectively manage the excess PbI2. Dec-oxoG NSs provide anchoring sites to bind the excess PbI2 and passivate perovskite grain boundaries, thereby reducing charge recombination loss and significantly boosting the extraction of free electrons. The inclusion of Dec-oxoG NSs leads to a PCE of 23.7 % in inverted (p-i-n) PSCs. The devices retain 93.8 % of their initial efficiency after 1,000 hours of tracking at maximum power points under continuous one-sun illumination and exhibit high stability under thermal and ambient conditions. 相似文献