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排序方式: 共有155条查询结果,搜索用时 31 毫秒
101.
Anshul Sharma Abdollah Neshat Cory J. Mahnen Alek d. Nielsen Jacob Snyder Tory L. Stankovich Benjamin G. Daum Emily M. LaSpina Gabrielle Beltrano Yunxiang Gao Shuo Li Byung‐Woo Park Robert J. Clements Ernest J. Freeman Christopher Malcuit Jennifer A. McDonough LaShanda T. J. Korley Torsten Hegmann Elda Hegmann 《Macromolecular bioscience》2015,15(2):292-292
102.
Biocompatible,Biodegradable and Porous Liquid Crystal Elastomer Scaffolds for Spatial Cell Cultures 下载免费PDF全文
Anshul Sharma Abdollah Neshat Cory J. Mahnen Alek d. Nielsen Jacob Snyder Tory L. Stankovich Benjamin G. Daum Emily M. LaSpina Gabrielle Beltrano Yunxiang Gao Shuo Li Byung‐Wook Park Robert J. Clements Ernest J. Freeman Christopher Malcuit Jennifer A. McDonough LaShanda T. J. Korley Torsten Hegmann Elda Hegmann 《Macromolecular bioscience》2015,15(2):200-214
103.
The high-frequency modulation characteristics of GaAs-based bipolar cascade vertical cavity surface-emitting lasers operating at 980 nm with GaAs tunnel junctions and p-doped Al0.98Ga0.02As oxide apertures have been measured. We achieve -3 dB laser output modulations of 6.5 GHz for two-stage and 9.4 GHz for three-stage devices in response to small-signal current injection at an operating temperature of -50 degrees C. 相似文献
104.
Windmiller JR Bandodkar AJ Valdés-Ramírez G Parkhomovsky S Martinez AG Wang J 《Chemical communications (Cambridge, England)》2012,48(54):6794-6796
The realization of epidermal chemical sensing requires a fabrication methodology compatible with the non-planarity and irregularities of the human anatomy. This communication describes the development of printed temporary transfer tattoo (T3) electrochemical sensors for physiological and security monitoring of chemical constituents leading to the demonstration of 'electronic skin'. 相似文献
105.
106.
107.
108.
A. Fix G. Ehret J. Löhring D. Hoffmann M. Alpers 《Applied physics. B, Lasers and optics》2011,102(4):905-915
A diode-pumped, single-frequency laser system emitting at 935 nm has recently been developed to serve as the transmitter for water vapor differential absorption lidar (DIAL) measurements. This laser uses Nd:YGG (Y3Ga5O12) as the active medium and emits radiation directly at 935 nm without the need of additional frequency conversion processes. The system was diode-pumped at 806 nm and was built up in a master-oscillator-power-amplifier configuration. It generates more than 30 mJ of pulse energy at 100 Hz repetition rate with a beam quality (M 2) of better than 1.4. Since water vapor DIAL demands for stringent requirements of the spectral properties those were carefully investigated in the scope of this paper. Single-frequency operation is achieved by injection seeding and active length control of the oscillator cavity. The range of continuously tunable single-frequency radiation extends to ~0.4 nm centered around 935.31 nm. Values of the spectral purity of >99.996% were determined using long-pass absorption measurements in the atmosphere exceeding the requirements by a large margin. Finally, for the first time water vapor DIAL measurements were performed using a Nd:YGG laser. The reported results show much promise of these directly pumped lasers at 935 nm for future spaceborne but also airborne water vapor lidar systems. 相似文献
109.
Gabrielle Viennet 《Probability Theory and Related Fields》1997,107(4):467-492
This paper investigates the problem of density estimation for absolutely regular observations. In a first part, we state
two important results: a new variance inequality and a Rosenthal type inequality. This allows us to study the ?
p
-integrated risk, p≧ 2, of a large class of density estimators including kernel or projection estimators. Under the summability condition on the
mixing coefficients ∑
k≧ 0
(k+1)
p− 2
β
k
<∞, the rates obtained are those known to be optimal in the independent setting.
Received: 17 October 1995 / In revised form: 26 October 1996 相似文献
110.
Hoshin V. Gupta Mohammad Reza Ehsani Tirthankar Roy Maria A. Sans-Fuentes Uwe Ehret Ali Behrangi 《Entropy (Basel, Switzerland)》2021,23(6)
We develop a simple Quantile Spacing (QS) method for accurate probabilistic estimation of one-dimensional entropy from equiprobable random samples, and compare it with the popular Bin-Counting (BC) and Kernel Density (KD) methods. In contrast to BC, which uses equal-width bins with varying probability mass, the QS method uses estimates of the quantiles that divide the support of the data generating probability density function (pdf) into equal-probability-mass intervals. And, whereas BC and KD each require optimal tuning of a hyper-parameter whose value varies with sample size and shape of the pdf, QS only requires specification of the number of quantiles to be used. Results indicate, for the class of distributions tested, that the optimal number of quantiles is a fixed fraction of the sample size (empirically determined to be ), and that this value is relatively insensitive to distributional form or sample size. This provides a clear advantage over BC and KD since hyper-parameter tuning is not required. Further, unlike KD, there is no need to select an appropriate kernel-type, and so QS is applicable to pdfs of arbitrary shape, including those with discontinuous slope and/or magnitude. Bootstrapping is used to approximate the sampling variability distribution of the resulting entropy estimate, and is shown to accurately reflect the true uncertainty. For the four distributional forms studied (Gaussian, Log-Normal, Exponential and Bimodal Gaussian Mixture), expected estimation bias is less than 1% and uncertainty is low even for samples of as few as data points; in contrast, for KD the small sample bias can be as large as and for BC as large as . We speculate that estimating quantile locations, rather than bin-probabilities, results in more efficient use of the information in the data to approximate the underlying shape of an unknown data generating pdf. 相似文献