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Nb-Ti微合金钢力学性能的预报模型 总被引:3,自引:0,他引:3
根据Nb Ti高强度低合金钢 (0 0 8%~ 0 11%C ,0 0 1%~ 0 0 4 %Nb ,0 0 1%~ 0 2 3%Ti)板材实际生产数据 ,采用多元逐步线性回归 ,得出钢板屈服强度σs(MPa)和抗拉强度σb(MPa)的数学模型 :σs=2 94 0 1Wc+74 7 89WNb+10 2 1 0 9WTi- 0 17Tc+5 95 99;σb=135 6 73WNb+136 1 39WTi- 0 0 1b - 1 6 9h +44 2 4 3(Wc,WNb,WTi为成分质量分数 / % ;Tc 为卷取温度 ;b为成品板宽 ;h为成品板厚 )。同时建立了BP神经网络预报模型 ,两种模型均具有较好的预报精度 ,神经网络预测值与实测值之间的相对误差小于± 10 %。 相似文献
3.
Yang Lv Zhenzhang Li Yahong Jin Haoyi Wu Chuanlong Wang Guifang Ju Li Chen Zhengfa Hu Yihua Hu 《Ceramics International》2019,45(5):5971-5980
Luminescent material Ca2Ba3(PO4)3F:Eu2+ displays green emitting in the range of 400–700?nm, which is ascribed to the 4f65d1 →4f7 transition of Eu2+ ions. Amazingly, the body color of the samples can be changed between colorless and green upon alternative UV and visible light irradiation/heating treatment with robust fatigue resistance due to photochromism. The photochromic effect strongly depends on the Eu2+ doping concentration. After remote-controlled short-UV irradiation, the overall Eu2+ emission intensity presents a significant decrease, and inversely, exhibits an increase to the initial level after illuminated by longer wavelength light or heat treatment. Moreover, the fluorescence lifetime also can be regulated reversibly, of which the regulation degree depends on the short-UV irradiation and longer wavelength illumination time/heating temperature. A schematic diagram based on energy levels is proposed to illustrate the photochromism mechanism. 相似文献
4.
Experiments in materials science investigating cubic crystalline structures often collect data which are in truth equivalence classes of crystallographically symmetric orientations. These intend to represent how lattice structures of particles are orientated relative to a reference coordinate system. Motivated by a materials science application, we formulate parametric probability models for “unlabeled orientation data.” This amounts to developing models on equivalence classes of three-dimensional rotations. We use a flexible existing model class for random rotations (called uniform-axis-random-spin models) to induce probability distributions on the equivalence classes of rotations. We develop one-sample Bayesian inference for the parameters in these models, and compare this methodology to some likelihood-based approaches. We also contrast the new parametric analysis of unlabeled orientation data with other analyses that proceed as if the data have been preprocessed into honest orientation data. Supplementary materials for this article are available online. 相似文献
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In this paper, we propose a minimum projected-distance test for parametric single-index regression models when the predictors are measured with Berkson errors. This test asymptotically behaves like a locally smoothing test as if the null model were with one-dimensional predictor, and is omnibus to detect all global alternative models. The test can also detect local alternative models that converge to the null model at the fastest rate that the existing locally smoothing tests with one-dimensional predictor can achieve. Therefore, the proposed test has potential for alleviating the curse of dimensionality in this field. We also give two bias-correction methods to center the test statistic. Numerical studies are conducted to examine the performance of the proposed test. 相似文献
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结合静电和电容传感技术各自的特点,提出了阵列式静电-电容传感器用于气固两相流中固相颗粒的局部速度、局部浓度以及局部流量测量。利用静电极片阵列与电容极片阵列获取管道内颗粒的速度分布与浓度分布,进而计算出颗粒的局部流量。该阵列式传感器参数测量的准确性直接取决于它的空间灵敏度分布特性。对静电极片阵列和电容极片阵列的灵敏度特性进行了研究。首先,建立了静电极片阵列的三维静电场模型,通过有限元法分析静电极片阵列的结构参数(电极长度、电极覆盖角等)对传感器灵敏度特性的影响;然后根据电磁场理论建立电容极片阵列的数学模型,并对其进行数值计算,研究管道厚度、管道介电常数、电极覆盖角等参数对传感器灵敏度特性的影响;最后搭建了传动带装置进行了实验研究,实验结果证实了模拟结果的准确性,为阵列式静电-电容传感器的优化设计提供理论依据。 相似文献
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以中国石化齐鲁分公司塑料厂LLDPE装置(简称齐鲁LLDPE装置)APC项目的实施为例,讨论在反应器控制中经常使用的产品质量控制目标函数的一般形式及一些问题的解决方法。 相似文献
10.
Cong Zhang Chuanlong Zhao Haiqing Yin Xuanhui Qu Yong Du 《Journal of Phase Equilibria and Diffusion》2018,39(6):766-777
The C-Mo-Zr system was assessed by means of the CALPHAD approach. All of the phase equilibria available from the literature were critically reviewed. The liquid was modeled as substitutional solution phase, while the carbides including fcc-(Mo,Zr)C1?x, bcc-(Mo), bcc-(Zr), hcp-Mo2C, hcp-(Zr) and η-MoC were described by using corresponding sublattice models. The laves-Mo2Zr and shp-MoC phases were considered as binary compounds with no solubility for the third component. The existence of ternary phase was not reported in this system. The modeling of C-Mo-Zr ternary system covers the entire composition and temperature ranges, and a set of self-consistent thermodynamic parameters for the C-Mo-Zr system was systematically optimized. Comprehensive comparisons between the calculated and reported phase diagram data show that the reliable information is satisfactorily accounted for by the present modeling. The liquidus projection and reaction scheme of the C-Mo-Zr system were also generated based on the present thermodynamic assessment. 相似文献