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991.
黎航 杨冬 李三伟 况龙钰 李丽灵 袁铮 张海鹰 于瑞珍 杨志文 陈韬 曹柱荣 蒲昱东 缪文勇 王峰 杨家敏 江少恩 丁永坤 胡广月 郑坚 《物理学报》2018,67(23):235201-235201
激光间接驱动惯性约束聚变实验中,黑腔内情况复杂,在激光烧蚀和辐射烧蚀等的驱动下,光斑区、冕区、纯辐射烧蚀区、射流区的多种等离子体以不同规律运动.发展了X光双能段窄能带的时间分辨成像方法,用以观测黑腔内多种等离子体的运动情况.在真空黑腔中观测到清晰的射流,分析了射流产生机制及其速度;在黑腔中充气,能有效消除射流和抑制冕区等离子体运动,但两种物质界面处可能会出现流体力学不稳定性等现象,分析了界面处的压力平衡关系和密度陡变情况. 相似文献
992.
ZHU Xia KUANG Le-Man 《理论物理通讯》2008,49(1):111-116
In this paper, we investigate the quantum Stackelberg duopoly (QSD) game in the noise environment with the depolarizing channel expressed by the Kraus-operator representation. It is found that the presence of the damping in the depolarizing channel always leads to the decrease of the quantities of the moves and payoffs of the two players in the QSD game. It is indicated that under certain conditions the first-mover advantage in the QSD game can be weakened due to the presence of the damping in the depolarizing channel. 相似文献
993.
N.M. Liao W. Li Y.D. Jiang Y.J. Kuang K.C. Qi Z.M. Wu S.B. Li 《Applied Physics A: Materials Science & Processing》2008,91(2):349-352
The ordering evolution of the amorphous network of a-Si:H thin films with increasing initial silane-gas temperatures was investigated
by Raman spectroscopy. The results show that there exists a gradual ordering of the amorphous network, both in the near surface
and interior region on increasing the silane-gas temperature. In addition, the increase in the gas temperature leads to an
improved ordering of amorphous network on the short and intermediate scales towards the surface of a-Si:H thin films. Post-annealing
at 250 °C for 3 h mainly leads to a short and intermediate range improvement in the interior region of the films. Our present
results suggest that a-Si:H thin films with better quality could be deposited at higher silane-gas temperature.
PACS 63.50.+x; 61.43.-j; 75.40.-s 相似文献
994.
995.
Huang Jin-Ling Kuang Xiao-Yu Mao Ai-Jie Wang Hui 《Journal of Physics and Chemistry of Solids》2008,69(4):913-917
The local lattice structure distortions for YAG and YGG systems doped with Cr3+ have been investigated by the d3 configuration complete energy matrices which contain the Zeeman energy besides the electron–electron interaction, the trigonal crystal field as well as the spin–orbit coupling interaction. The local lattice structure parameters R and θ of (CrO6)9− complex are determined for Cr3+ in YAG and YGG systems, respectively. The calculated results show that the local lattice structures have expansion distortions, which almost tend to the same after distortions. Meanwhile, the EPR parameter D, g factors (g||, g) and optical spectrum of these systems have been interpreted uniformly by quantitative calculation. It is shown that the effect of the orbit reduction factor k on g factors (g||, g) cannot be ignored. 相似文献
996.
The paper investigates the chaotic flexural oscillations of the spinning nanoresonator. The influence of cubic nonlinearity
arising from the van der Waals interactions between two neighboring layers of carbon nanotubes on the structural oscillations
of the system is considered. The integral–differential equations describing the flexural displacements of the nanoresonator
are discretized into two coupled Duffing-type equations using the Galerkin–Ritz procedures. The linear stiffness can be either
positive or negative, depending on the amplitudes of the linear trap rigidity arising from both the van der Waals interactions
and the axial tensile loads. The chaotic flexural oscillations of the appropriately excited spinning nanoresonator are predicted
theoretically. Using the Nayfeh–Mook multiscale perturbation algorithms, the coupled Duffing-type equations with linear positive
stiffness may be transformed into autonomous equations of slowly modulated amplitudes whose equilibrium points and chaotic
dynamics are investigated numerically. The potential chaotic oscillations of the elastic nanoresonator can be determined by
the Melnikov–Holmes–Marsden (MHM) integral associated with the homoclinic/heteroclinic solutions of the disturbed Hamiltonian
systems with linear negative stiffness. The findings are validated through the Poincare sections and Lyapunov exponents. 相似文献
997.
Haoxi Zhou Yachao Liu Xiaojun Zhang Kuang Chen Yuan Li Xiaodan Xu Baixuan Xu 《Molecules (Basel, Switzerland)》2022,27(9)
Purpose: With the increasing detection rate of early prostate cancer (PCa), the proportion of surgical treatment is increasing. Surgery is the most effective treatment for PCa. Precise targeting of tumors during surgery can reduce the incidence of positive surgical margins (PSMs) and preserve the neurovascular bundles (NVBs) as much as possible. The objective of this study was to synthesize a PSMA fluorescent probe (PSMA-Cy5) and verify the targeting specificity of the probe for prostate cancer, thereby providing a theoretical basis for the development of PSMA fluorescent probes for clinical application in the future. Methods: In this study, a novel water-soluble 3H-indocyanine-type bioluminescent dye-Cy5-labeled prostate-specific membrane antigen (PSMA) ligand (PSMA-Cy5) was synthesized by liquid phase synthesis. The PSMA ligand was developed based on the glutamine-urea-lysine (Glu-urea-Lys) structure. The new fluorescent probe was evaluated in vitro and in vivo, and its safety was evaluated. Confocal microscopy was used to observe the binding uptake of PSMA-Cy5 with PSMA (+) LNCaP cells, PSMA (-) PC3 cells and blocked LNCaP cells. In in vivo optical imaging studies, the targeting specificity of PSMA (+) 22Rv1 tumors to probe binding was validated by tail vein injection of PSMA-Cy5. The safety of the PSMA-Cy5 probe was evaluated by histopathological analysis of mouse organs by a single high-dose tail vein injection of PSMA-Cy5. Results: In vitro fluorescence cell uptake experiments showed that the binding of PSMA-Cy5 to LNCaP cells has targeting specificity. PC3 cells and blocked LNCaP cells showed almost no uptake. The results of in vivo optical imaging studies showed that the tumor-to-background ratio in the 22Rv1 group was 3.39 ± 0.47; in the 22Rv1 blocking group it was 0.78 ± 0.15, and in the PC3 group it was 0.94 ± 0.09, consistent with the in vitro results. After a high-dose injection of PSMA-Cy5, there were no abnormalities in the tissues or organs of the mice. The probe showed good safety. Conclusions: PSMA-Cy5 is a probe with good targeting specificity and low toxicity that can accurately visualize tumors in vivo. This study has an important reference value for the development of PSMA fluorescent probes. In the future, it can be applied to precise tumor imaging during radical prostatectomy to reduce the incidence of postoperative PSM. 相似文献
998.
Peihua Tang Dandan Liu Zheli Wu Hui Cui Ren Zhang Zaoyuan Kuang 《Molecules (Basel, Switzerland)》2022,27(9)
This study aimed to investigate the inhibitory effects and mechanism of diaporthein B (DTB), a natural compound extracted from the fungus Penicillium sclerotiorum GZU-XW03-2, on human colon cancer cells. The inhibitory effect of DTB at different concentrations on the proliferation of colon cancer cells HCT116 and LOVO was detected at 24 and 48 h. The effect of cell migration and clone formation ability were detected by cell scratch and plate cloning experiments. Morphological changes were observed by Hoechst 33342 and Annexin-V/PI staining, and flow cytometry was used to detect the proportion of apoptotic cells. DTB significantly inhibited colon cancer cell proliferation, migration, and apoptosis in a dose-dependent manner without significant effects on normal colonic epithelial cells NCM460. The IC50 inhibition effect can be achieved after treatment with 3 μmol/L DTB for 24 h. Compared with the blank group, the migration and clonal-forming ability of colon cancer cells in the DTB group was significantly decreased (p < 0.01), while the apoptotic cells were significantly increased (p < 0.01) in a concentration-dependent manner. DTB can inhibit the proliferation and migration of human colon cancer cells HCT116 and LOVO and promote the apoptosis of human colon cancer cells. 相似文献
999.
1000.
三羰基全甲基硅基环戊二烯基钼衍生物的合成与表征 总被引:2,自引:0,他引:2
通过三羰基(五甲基二硅基)环戊二烯基钼负离子盐与卤代烃(EtI,PhCH2Cl,ClCH2COOEt,I(CH2)4I)进行基化反应合成其烷基钼化合物。用六甲基三硅二氧烷桥联双(三羰基环戊二烯基钼)负离子经冰醋酸处理,硫酸铁氧化偶联成钼-钼键双核化合物,经碘裂解后钼-钼键生成六甲基三硅二氧烷桥联双(三羰基环戊二烯基碘钼)化合物。以元素分析,IR和1HNMR谱表征了化合物的结构。 相似文献