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91.
Single‐Crystal‐Like Organic Thin‐Film Transistors Fabricated from Dinaphtho[2,3‐b:2′,3′‐f]thieno[3,2‐b]thiophene (DNTT) Precursor–Polystyrene Blends 下载免费PDF全文
92.
Ryuta Shigefuku Hideaki Takahashi Hiroyasu Nakano Tsunamasa Watanabe Kotaro Matsunaga Nobuyuki Matsumoto Masaki Kato Ryo Morita Yousuke Michikawa Tomohiro Tamura Tetsuya Hiraishi Nobuhiro Hattori Yohei Noguchi Kazunari Nakahara Hiroki Ikeda Toshiya Ishii Chiaki Okuse Shigeru Sase Fumio Itoh Michihiro Suzuki 《International journal of molecular sciences》2016,17(9)
The progression of chronic liver disease differs by etiology. The aim of this study was to elucidate the difference in disease progression between chronic hepatitis C (CHC) and nonalcoholic fatty liver disease (NAFLD) by means of fibrosis markers, liver function, and hepatic tissue blood flow (TBF). Xenon computed tomography (Xe-CT) was performed in 139 patients with NAFLD and 152 patients with CHC (including liver cirrhosis (LC)). The cutoff values for fibrosis markers were compared between NAFLD and CHC, and correlations between hepatic TBF and liver function tests were examined at each fibrosis stage. The cutoff values for detection of the advanced fibrosis stage were lower in NAFLD than in CHC. Although portal venous TBF (PVTBF) correlated with liver function tests, PVTBF in initial LC caused by nonalcoholic steatohepatitis (NASH-LC) was significantly lower than that in hepatitis C virus (C-LC) (p = 0.014). Conversely, the liver function tests in NASH-LC were higher than those in C-LC (p < 0.05). It is important to recognize the difference between NAFLD and CHC. We concluded that changes in hepatic blood flow occurred during the earliest stage of hepatic fibrosis in patients with NAFLD; therefore, patients with NAFLD need to be followed carefully. 相似文献
93.
Fracture behaviour and numerical study of resistance spot welded joints in high-strength steel sheet
Teruki Sadasue Satoshi Igi Koichi Taniguchi Rinsei Ikeda Kenji Oi 《Welding International》2016,30(8):602-613
Cross tension tests of resistance spot welded joints with varying nugget diameter were carried out using 980 MPa high strength steel sheet of 1.6 mm thickness. In proportion, as nugget diameter increased from 3√t to 5√t (where t is thickness), cross tension strength (CTS) increased while fracture morphology simultaneously transferred from interface fracture to full plug fracture. In cases of interface fracture, circumferential crack initiation due to separation of the corona bond arose at an early stage of loading. The crack opening process without propagation was recognized until just before fracture and then the crack propagated to the nugget immediately in a brittle manner around CTS. In full plug fracture, main ductile crack initiation from the notch-like part at the end of sheet separation occurred with the sub-crack initiated at an early stage. The ductile crack propagated toward the HAZ and base material to form full plug fracture. The mode I stress intensity factor was considered as a suitable fracture parameter because the circumferential crack behaved pre-crack for brittle fracture in the nugget region at the final stage. Based on the FE analysis, the mode I stress intensity factor was calculated as 116 MPa √m at CTS as fracture toughness for the nugget. With respect to full plug fracture, ductile crack initiation behaviour from the notch-like part was expressed by concentration of equivalent plastic strain. On the assumption that the ductile crack arose in critical value of equivalent plastic strain, the value was calculated as 0.34 by FE analysis. Reasonable interpretation for interface fracture and full plug fracture in the resistance spot welded joint was proposed due to first crack initiation by stress concentration, brittle fracture by using mode I stress intensity factor, and ductile crack initiation by using equivalent plastic strain. 相似文献
94.
The solvothermal synthesis of highly luminescent and homogeneous Gd2O3:Eu3+ nanophosphor using diethylene glycol as medium, followed by controlled combustion with citric acid as fuel is reported. The influence of concentrations of carboxylic acid and metal cations on the structure, morphology and luminescence properties are investigated in detail. The microscopic investigations indicate the nanocrystalline nature and the strong influence of cation concentration on the size, shape and agglomeration of the particles. It is found that increase in concentration of metal cations lead to the reduction in agglomeration of nanophosphors. The large value of intensity parameter Ω2, suggested that Eu3+ ions reside in a more asymmetric environment, resulted in intense emission due to 5D0–7F2 electric dipole transition. Emission decay analysis of the samples exhibited one exponential nature. The samples prepared under optimum conditions showed a quantum efficiency of 78.63% and a moderately high life time of 1.217 ms. 相似文献
95.
Takahiro Funami Sakie Noda Makoto Nakauma Sayaka Ishihara Rheo Takahashi Saphwan Al-Assaf Shinya Ikeda Katsuyoshi Nishinari Glyn O. Phillips 《Food Hydrocolloids》2009,23(2):548-554
Aqueous solutions of gellan gum with comparable molecular mass but with different acyl contents were investigated by atomic force microscopy and rheological measurements in the presence of sodium chloride (NaCl). Results obtained were discussed in relation to our previous report using potassium chloride (KCl) as an added salt. For a low-acyl sample, continuous fibrous network structures were identified microscopically as in the case of KCl. The network structures were more heterogeneous than those formed with KCl in terms of the height distribution of molecular assemblies. Rheological thermal hysteresis between sol–gel transitions was detected as in the case of KCl. The storage modulus (G′) of the gelled system was ca. 15% of the corresponding data with KCl at 20 °C. For a high-acyl sample, no continuous network structures were identified but branches with observable ends were identified as in the case of KCl. The hysteresis was less evident than the corresponding data with KCl and for the low-acyl sample with NaCl. Also, G′ values at 20 °C were ca. 30% and 20% of the corresponding data with KCl and for the low-acyl sample with NaCl, respectively. Continuousness and homogeneity of network structures related to the hysteresis and elasticity of the system, respectively. 相似文献
96.
Tsuyoshi Nomura Masahiro Ikeda Seiji Ishiyama Kazuhide Mita Toshiki Tamura Takahiro Okada Kazuhito Fujiyama Akihiro Usami 《Journal of Bioscience and Bioengineering》2010,110(4):386-391
In insects, β-N-acetylglucosaminidase (GlcNAcase) participates in critical physiological processes such as fertilization, metamorphosis, and glycoconjugate degradation. Insects produce glycoproteins carrying paucimannosidic-type N-glycans, the terminal GlcNAc residue of which is cleaved by a GlcNAc-linkage specific GlcNAcase, also known as the fused lobes (FDL) protein. To obtain information on the structure of GlcNAcases and insight into their contribution to physiological processes, we cloned Bombyx mori FDL (BmFDL) from silkworm larvae. The full-length cDNA (1.9 kb) encoded a protein of 633 amino acids with 42% amino acid sequence identity to Drosophila melanogaster FDL (DmFDL). Recombinant BmFDL cleaved only β-1,2-linked GlcNAc residues from the α-1,3 branch of biantennary N-glycan. This substrate specificity was similar to that of DmFDL. Microsomal FDL activity was inhibited by anti-BmFDL antibodies. Taken together, our results suggest that BmFDL is a N-glycan-processing GlcNAcase in B. mori. 相似文献
97.
98.
Okabe Y Watanabe A Shingu H Kushibiki S Hodate K Ishida M Ikeda S Takeda T 《Meat science》2002,62(4):428-462
Relationships between α-tocopherol concentration in the muscle and development of lipid oxidation or volatiles in raw venison were studied. Fourteen Japanese Shika Deer (Cervus nippon) were fed various amounts (0–3.0 g of α-tocopheryl acetate per animal) during the different periods (0–37 days) and then M. longissimus thoracium et lumborum (LD muscles) with a range of α-tocopherol concentrations (4.1–15.1 mg/kg tissue) were obtained. For stabilizing the lipid during storage for 11 days under air, over ca. 9 mg of α-tocopherol per kg tissue were required based on levels of 2-thiobarbituric acid reacting substances (TBARS) numbers. Nine compounds were identified in headspace volatiles, and one of the volatiles was hexanal which has been recognized as off-flavour component. For depressing the hexanal evolution, at least ca. 9 mg of α-tocopherol per kg tissue were also required for 11 days’ storage. This value was much higher than other species. The reasons for higher requirement of α-tocopherol were possibly due to the higher concentration of unsaturated fatty acid and myoglobin in venison. 相似文献
99.
Y. Ikeda T. Shibutani M. Sasaki S. Shoji N. Yamada 《Journal of Materials Science》2002,37(18):3861-3866
Graft polymerization of methacrylic acid onto ABS resin was carried out using BPO as an initiator in THF solution. Degree of grafting increased with reaction time and reached 35% in 10 hrs. Carboxyl groups were converted to carboxylates (metal salts) by refluxing MAA-g-ABS and the metal acetate in THF. In the solid graft polymers in solid, the infrared absorption of the asymmetrical C= O vibration of the carboxylic acid shifted to lower wavenumbers with increasing metal ion concentration. The absorption peak for the carboxylate anion is shifted to higher wavenumbers with the increase of alkali metal ion concentration, however, for the Mg2+ salt, it is shifted to lower wavenumbers. The surface and volume resistivities of the K+ and Na+ salts of MAA-g-ABS were 9.0 × 109 and 9.5 × 109 at 80% neutralization, respectively, and decreased with alkali metal ion concentration. The electric resistance of Li+, Mg2+ and Zn2+ salts decreased only slightly. The modulus of the K+ salt of MAA-g-ABS decreased with neutralization, whereas in Li+, Mg2+ and Zn2+ salts, the modulus increased with increasing metal ion concentration. 相似文献
100.
The present study was undertaken to examine the effects of various transition metal ion chelators, both polyaminocarboxylates (including nitrilotriacetate (NTA), ethylenediaminediacetate (EDDA), ethyleneglycolbistetraacetate (EGTA), ethylenediaminetetraacetate (EDTA) and diethylenetriaminepentaacetate (DTPA)) and non-polyaminocarboxylates (dipicolinic acid and deferoxamine), on the development in vitro of one-cell ICR strain mouse embryos to the four-cell and blastocyst stages. The order of stability constants of polyaminocarboxylates for transition metal ions such as zinc, copper and iron is as follows: NTA < or = EDDA < EGTA < EDTA < DTPA. Addition of 10 or 100 micromol polyaminocarboxylates x l(-1) to the medium significantly enhanced the development of most one-cell embryos (66-88%) beyond the two-cell stage compared with that (< 25%) in medium without polyaminocarboxylates. Although EDDA, EDTA and DTPA at 10 micromol x l(-1) induced the development of most one-cell embryos to the four-cell stage and beyond, a higher concentration (100 micromol x l(-1)) of NTA and EGTA was required to obtain a similar result. Therefore, the ability of polyaminocarboxylates to overcome the two-cell block is not correlated with their potency to chelate transition metal ions. In contrast, the non-polyaminocarboxylates dipicolinic acid and deferoxamine, at 10 and 100 micromol x l(-1), did not have the same effect. Taken together, the results indicate that the ability of polyaminocarboxylates to overcome the two-cell block in embryo development is due to some common feature or features other than the ability to chelate transition metal ions. 相似文献