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61.
Pengcheng Nie Fangfang Qu Lei Lin Yong He Xuping Feng Liang Yang Huaqi Gao Lihua Zhao Lingxia Huang 《International journal of molecular sciences》2021,22(7)
Molecular spectroscopy has been widely used to identify pesticides. The main limitation of this approach is the difficulty of identifying pesticides with similar molecular structures. When these pesticide residues are in trace and mixed states in plants, it poses great challenges for practical identification. This study proposed a state-of-the-art method for the rapid identification of trace (10 mg·L−1) and multiple similar benzimidazole pesticide residues on the surface of Toona sinensis leaves, mainly including benzoyl (BNL), carbendazim (BCM), thiabendazole (TBZ), and their mixtures. The new method combines high-throughput terahertz (THz) imaging technology with a deep learning framework. To further improve the model reliability beyond the THz fingerprint peaks (BNL: 0.70, 1.07, 2.20 THz; BCM: 1.16, 1.35, 2.32 THz; TBZ: 0.92, 1.24, 1.66, 1.95, 2.58 THz), we extracted the absorption spectra in frequencies of 0.2–2.2 THz from images as the input to the deep convolution neural network (DCNN). Compared with fuzzy Sammon clustering and four back-propagation neural network (BPNN) models (TrainCGB, TrainCGF, TrainCGP, and TrainRP), DCNN achieved the highest prediction accuracies of 100%, 94.51%, 96.26%, 94.64%, 98.81%, 94.90%, 96.17%, and 96.99% for the control check group, BNL, BCM, TBZ, BNL + BCM, BNL + TBZ, BCM + TBZ, and BNL + BCM + TBZ, respectively. Taking advantage of THz imaging and DCNN, the image visualization of pesticide distribution and residue types on leaves was realized simultaneously. The results demonstrated that THz imaging and deep learning can be potentially adopted for rapid-sensing detection of trace multi-residues on leaf surfaces, which is of great significance for agriculture and food safety. 相似文献
62.
Ali Raza Wei Su Ang Gao Sundas Saher Mehmood Muhammad Azhar Hussain Wenlong Nie Yan Lv Xiling Zou Xuekun Zhang 《International journal of molecular sciences》2021,22(8)
Catalase (CAT) is an antioxidant enzyme expressed by the CAT gene family and exists in almost all aerobic organisms. Environmental stresses induce the generation of reactive oxygen species (ROS) that eventually hinder plant growth and development. The CAT enzyme translates the hydrogen peroxide (H2O2) to water (H2O) and reduce the ROS levels to shelter the cells’ death. So far, the CAT gene family has not been reported in rapeseed (Brassica napus L.). Therefore, a genome-wide comprehensive analysis was conducted to classify the CAT genes in the rapeseed genome. The current study identified 14 BnCAT genes in the rapeseed genome. Based on phylogenetic and synteny analysis, the BnCATs belong to four groups (Groups I–IV). A gene structure and conserved motif analysis showed that Group I, Group II, and Group IV possess almost the same intron/exon pattern, and an equal number of motifs, while Group III contains diverse structures and contain 15 motifs. By analyzing the cis-elements in the promoters, we identified five hormone-correlated responsive elements and four stress-related responsive elements. Further, six putative bna-miRNAs were also identified, targeting three genes (BnCAT4, BnCAT6, and BnCAT8). Gene ontology (GO) enrichment analysis showed that the BnCAT genes were largely related to cellular organelles, ROS response, stimulus response, stress response, and antioxidant enzymes. Almost 10 BnCAT genes showed higher expression levels in different tissues, i.e., root, leaf, stem, and silique. The expression analysis showed that BnCAT1–BnCAT3 and BnCAT11–BnCAT13 were significantly upregulated by cold, salinity, abscisic acid (ABA), and gibberellic acid (GA) treatment, but not by drought and methyl jasmonate (MeJA). Notably, most of the genes were upregulated by waterlogging stress, except BnCAT6, BnCAT9, and BnCAT10. Our results opened new windows for future investigations and provided insights into the CAT family genes in rapeseed. 相似文献
63.
Nie Zuoren Zhang Xinming Yin Zhimin Department of Materials Science Engineering Central South University of Technology Changsha 《中国有色金属学会会刊》1997,(3)
MICROSTRUCTURESANDTEXTURESINCOLDROLLEDALUMINIUMSTRIP①NieZuoren,ZhangXinming,YinZhiminDepartmentofMaterialsScienceandEngineri... 相似文献
64.
history dependent forming limits of sheet metals are computed by examining the role of rate sensitivity of flow stress in forming limits for anisotropic materials. Assuming that necking or nonuniform deformation is caused by initial heterogeneity, the forming limits are computed by considering the flow theory and incorporating an isotropic hardening model for anisotropic materials. Representative results show some of the trends for changing forming limits with different parameters under complex nonproportional loading histories. The computed results agree well with published experimental data for different loading history, anisotropy, and rate sensitivity of sheet materials. 相似文献
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聚乙烯转光棚膜的加工及应用研究 总被引:8,自引:3,他引:8
本文对聚乙烯转光棚膜的加工和光转换剂的作用、配比关系及物理性能进行了讨论。 相似文献
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69.
以某混凝土重力坝非溢流坝段动力特性为背景,探讨流固耦合效应对结构自振特性的影响,运用大型有限元软件对结构自振特性进行分析计算,得出了流体对结构自振特性影响以及结构的固有频率,避免在运行过程中发生共振,造成对结构的破坏。 相似文献
70.
Poly(5‐bromoindole) (PBrI) films were synthesized electrochemically by direct oxidation of 5‐bromoindole in pure boron trifluoride diethyl etherate. The oxidation potential of 5‐bromoindole in this medium was measured to be only 0.97 V vs. saturated calomel electrode, which was lower than that determined in acetonitrile + 0.1 mol L?1 Bu4NBF4 (1.08 V). PBrI films obtained from this medium showed good electrochemical behavior and good thermal stability. Structural studies showed that the polymerization of 5‐bromoindole ring occurred at 2,3 position. As‐formed PBrI films were thoroughly soluble in strong polar solvent dimethylsulfoxide and partly soluble in tetrahydrofuran. Fluorescent spectral studies indicated that PBrI was a good blue‐light emitter. The excitation and emission spectra of PBrI showed a significant shift to longer wavelength compared with that of the monomer, consistent with the greater extent of electron delocalization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 539–547, 2006 相似文献