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51.
在JTAG(jointtestactiongroup)工业标准的基础上,采用了一种基于语音识别SoC(SystemonChip)调试的JTAG接口设计.该设计以求用最少的硬件开销,最简单灵活的方式,支持寄存器查看和设置、IP核程序流跟踪、代码覆盖率检查、代码分析、IP核扫描测试等功能.该设计已经应用于以OpenRISC为核心的语音识别SoC设计平台上.  相似文献   
52.
The effects of absolute energy calibration on BESⅢ physics are discussed in detail,which mainly involve the effects on τ mass measurement,cross section scan measurement,and generic error determination in other measurements.  相似文献   
53.
有限线状连续带电体二维平面电场的计算机模拟   总被引:2,自引:0,他引:2  
利用切线法和扫描法绘制一些有限线状连续带电体所在平面的电力线和等势线。  相似文献   
54.
提出了一种在视觉导引下的被动装配方法,该方法首先使用视觉进行粗定位,然后使用装配平台的扫描运动完成最后的装配,该方法克服了视觉装配误差大和被动装配时间长的缺点,集中了视觉装配速度快和被动装配精度高的优点,使得精确装配能够迅速完成。文中不仅给出了装配系统的模型,而且给出了空间点的矩阵变换,通过摄像机的特殊配置,使得矩阵变换非常简单。同时,对摄像机的最大成像误差进行了估计,为后面的装配平台运动提供依据。最后,给出了装配过程的实验结果,从装配过程所化的时间来看,该系统是可行的。  相似文献   
55.
探讨了当前网络安全技术,并提出了一种结合当前现有技术的新网络安全方案,详细地探讨了实施方法,给当前网络安全的研究提供了一个新的思路。  相似文献   
56.
Non-specific binding (NSB) of high-molecular-weight proteins onto electrode surfaces can complicate the application of electroanalytical techniques to clinical and environmental research, particularly in biosensor applications. We present herein various strategies to modify the surface of reticulated vitreous carbon (RVC) electrodes to suppress non-specific binding of biomolecules onto its surface. Non-specific binding and specific binding (SB) of two enzyme conjugates, neutravidin-alkaline phosphatase (NA-ALP) and biotinylated alkaline phosphatase (B-ALP), and also neutravidin itself, were studied using hydroquinone diphosphate (HQDP) as an enzyme substrate for ALP inside the pores of RVC electrodes that had been subjected to various modification schemes. The extent of NSB and SB of these biomolecules inside RVC pores was assessed by measuring the initial rate of generation of an electroactive product, hydroquinone (HQ), of the enzyme-catalyzed reaction, using linear scan voltammetry (LSV) for HQ detection. Electrodes functionalized with phenylacetic acid and poly(ethylene glycol) (PEG) showed low NSB and high SB (when biotin capture ligands were included in the modification scheme) in comparison with unmodified electrodes and RVC electrodes modified in other ways. A simple sandwich bioassay for neutravidin was performed on the RVC electrode with the lowest NSB. A concentration detection limit of 52 ± 2 ng mL−1 and an absolute detection limit of 5.2 ± 0.2 ng were achieved for neutravidin when this assay was performed using a 100 μL sample size.  相似文献   
57.
High-speed, wide-range wavelength scanning is demonstrated using a laser diode with an antireflection coating and an external cavity employing an acousto-optic deflector. The narrow spectral width of 0.2 nm observed in the experiment indicates the availability of a highly coherent laser beam. The scanning range of 15 nm under rapid modulation is confirmed in the prototype system. A tuning rate of more than 100 kHz is achieved without any mode hops. To the best of our knowledge, no such high-speed wavelength tuning based on an acousto-optical configuration has been demonstrated thus far.  相似文献   
58.
Real-world magnetic resonance imaging of the brain is affected by intensity nonuniformity (INU) phenomena which makes it difficult to fully automate the segmentation process. This difficult task is accomplished in this work by using a new method with two original features: (1) each brain tissue class is locally modeled using a local linear region representative, which allows us to account for the INU in an implicit way and to more accurately position the region's boundaries; and (2) the region models are embedded in the level set framework, so that the spatial coherence of the segmentation can be controlled in a natural way. Our new method has been tested on the ground-truthed Internet Brain Segmentation Repository (IBSR) database and gave promising results, with Tanimoto indexes ranging from 0.61 to 0.79 for the classification of the white matter and from 0.72 to 0.84 for the gray matter. To our knowledge, this is the first time a region-based level set model has been used to perform the segmentation of real-world MRI brain scans with convincing results.  相似文献   
59.

Purpose

This retrospective study was designed to evaluate the apparent diffusion coefficient (ADC) of line scan diffusion images (LSDI) in normal prostate and prostate cancer. Single-shot echo planner images (SS-EPI) were used for comparison.

Materials and Methods

Twenty prostate tumors were examined by conventional MRI in 14 patients prior to radical prostatectomy. All patients were examined with a 1.5-T MR imager (Signa CV/i ver. 9.1 GE Medical System Milwaukee, WI, USA). Diffusion-weighted MR imaging (DWI) using LSDI was performed with a pelvic phased-array coil, with b values of 5 and 800 s/mm2. DWI using SS-EPI was performed with a body coil, with b values of 0 and 800 s/mm2. The ADCs of each sequence for 14 normal prostate and 20 prostate cancers were histopathologically assessed. Signal-to-noise ratio (SNR) on DWI was estimated and compared for each sequence.

Results

The mean ADCs (±S.D.) of normal peripheral zones (PZ), transition zones (TZ) and cancer (in 10−3 mm2/s) that used LSDI were 1.42±0.12, 1.23±0.10 and 0.79±0.19, respectively. Those that used SS-EPI were 1.76±0.26, 1.38±0.20 and 1.05±0.27, respectively. Using unpaired t test (P<.05), we found a significant difference in each sequence between normal tissue (both PZ and TZ) and the cancer. Paired t test (P<.05) also registered a significant difference between LSDI and SS-EPI. Mean SNR for DWI using LSDI was 16.49±5.03, while the DWI using SS-EPI was 18.85±9.26. The difference between the SNR of each sequence was not statistically significant by paired t test.

Conclusion

We found that ADCs using LSDI and SS-EPI showed similar tendencies in the same patients. However, in all regions, LSDI ADCs had smaller standard deviations than SS-EPI ADCs.  相似文献   
60.
Elimination voltammetry with linear scan (EVLS) in connection with renewed mini‐ drop mercury electrodes provides valuable information about the character and kinetics of processes at electrode/electrolyte interfaces. Based on the experiment related to the hydrogen evolution, it is presented that the EVLS is more sensitive than other voltammetric methods. Using miniaturized mercury electrodes, the EVLS is capable of detecting the effect of spherical diffusion associated with both the scan rates and the size of an electrode drop.  相似文献   
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