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481.
Uchiyama Susumu; Hasegawa Jun; Tanimoto Yuko; Moriguchi Hiroshi; Mizutani Masayuki; Igarashi Yasuo; Sambongi Yoshihiro; Kobayashi Yuji 《Protein engineering, design & selection : PEDS》2002,15(6):455-461
Thermal stability was measured for variants of cytochrome c-551(PA c-551) from a mesophile, Pseudomonas aeruginosa, and a thermophiliccounterpart, Hydrogenobacter thermophilus cytochrome c-552 (HTc-552), by differential scanning calorimetry (DSC) at pH 3.6.The mutated residues in PA c-551, selected with reference tothe corresponding residues in HT c-552, were located in threespatially separated regions: region I, Phe7 to Ala/Val13 toMet; region II, Glu34 to Tyr/Phe43 to Tyr; and region III, Val78to Ile. The thermodynamic parameters determined indicated thatthe mutations in regions I and III caused enhanced stabilitythrough not only enthalpic but also entropic contributions,which reflected improved packing of the side chains. Meanwhile,the mutated region II made enthalpic contributions to the stabilitythrough electrostatic interactions. The obtained differencesin the Gibbs free energy changes of unfolding [ 相似文献
482.
Okamoto Yuko; Fukugita Masataka; Nakazawa Takashi; Kawai Hikaru 《Protein engineering, design & selection : PEDS》1991,4(6):639-647
Conformation of the C-peptide fragment of RNase A is calculatedby Monte Carlo simulated annealing. We adopt the total potentialenergy as given by the sum of generic interatomic energies whoseparameters are determined separately for each amino acid withoutreferring to the empirical structure of the C-peptide. The simulationis carried out in a completely unrestricted way without imposingany weight towards given final destinations. Starting from completelyrandom initial conformations and minimizing the total potentialenergy with respect to main-chain dihedral angles and side-chaintorsion angles, we have obtained partial -helix structure witha high probability ({small tilde}40%). The energetically mostfavourable structure exhibits a 2.5-turn -helix at the locationidentical with that of the 3-turn -helix in the native enzymemolecule. Classification of conformations obtained in the simulationinto clusters of similar structure shows that our simulationindeed predicts the -helix structure for the isolated C-peptidewith specific charged residues. The results of simulation withvarious amino acid substitutions are also found to be consistentwith the experimental implication for the importance of intramolecularionic interactions for -helix stability for this peptide. 相似文献
483.
Zhaohui ZHANG Zuxing ZHANG Yixin YIN Yuko UENO Rakchanok RUNGSAWANG Katsuhiro AJITO 《中国光电子学前沿》2009,2(3)
Terahertz (THz) absorption spectra have been applied to measure the compositions of amino acid samples.Because the concentration information about a specific composition is involved in its spectrum, keeping the spectrum length and dynamic range as wide as possible is essential for precise measurements.It is well known that a spectrum is always contaminated by apparatus noises.In this paper, we present a criterion for noise cutting based on wavelet transform, which usually extends the range determined by traditional threshold criterion.Finally, theimprovement on measurement precision shows the validity of the new criterion. 相似文献
484.
Toshio Kimura Yuko Miura Kaori Fuse 《International Journal of Applied Ceramic Technology》2005,2(1):15-23
Bulk BaTiO3 ceramics with 〈111〉-texture have been prepared by the modified templated grain growth method, using platelike Ba6 Ti17 O40 particles as templates, and the mechanism of texture development is examined. The Ba6 Ti17 O40 particles induce the abnormal growth of BaTiO3 grains, and a structure similarity between {001} of Ba6 Ti17 O40 and {111} of BaTiO3 gives 〈111〉-texture to abnormally grown BaTiO3 grains. Thus, the 〈111〉-texture develops in the BaTiO3 matrix. The use of platelike Ba6 Ti17 O40 particles has been extended to a 0.65Pb(Mg1/3 Nb2/3 )O3 –0.35PbTiO3 matrix, but the matrix phase is decomposed by extensive chemical reactions between the matrix and template phases. 相似文献
485.
To evaluate the nutritional advantages of quinoa seeds (Chenopodium quinoa Willd.) cultivated in Japan, antioxidative properties and flavonoid composition were determined and compared to corresponding data for conventionally-used cereals and pseudo-cereals, including quinoa seeds from South America. The antioxidant activities of these grains against DPPH radicals were strongly associated with the total phenolic content of the tested samples. The crude extracts of quinoa seeds cultivated in Japan exhibited higher antioxidative effects than those from South America and other cereals, excluding buckwheat. Four flavonol glycosides were isolated and identified from the Japanese quinoa seeds, and the chemical composition of the flavonoids – quercetin and kaempferol 3-O-(2″,6″-di-O-α-rhamnopyranosyl)-β-galactopyranosides (1 and 4), quercetin 3-O-(2″,6″-di-O-α-rhamnopyranosyl)-β-glucopyranoside (2), and quercetin 3-O-(2″-O-β-apiofuranosyl-6″-O-α-rhamnopyranosyl)-β-galactopyranoside (3) – was evaluated through quantitative determination. Trioside 2 was isolated for the first time from quinoa seeds. These glycosides were not detected in extracts from any of the tested grains except quinoa. The aglycone quercetin content of the Japanese quinoa seeds is higher than in the seeds from South America and buckwheat. The amounts of quercetin and kaempferol formed via acidic hydrolysis in quinoa are much higher than those of conventionally-used edible plants. The quinoa seeds cultivated in Japan are the most effective functional foodstuff – in terms of being a source of antioxidative and bioactive flavonoids – among cereals and pseudo-cereals. 相似文献
486.
Harada T Kawai T Sato H Yokoyama H Kumeda Y 《International journal of food microbiology》2012,156(2):161-167
Kudoa septempunctata is a newly identified myxosporean parasite that infects the trunk muscles of olive flounder (Paralichthys olivaceus) and a causative agent of the increasing number of foodborne gastroenteritis outbreaks with unknown etiology which have occurred in Japan over the last few years. Here, we developed a quantitative polymerase chain reaction (QPCR) assay for the detection of K. septempunctata 18S rDNA in olive flounder muscle tissue samples. Additionally, we compared the relative efficacy of four DNA extraction methods, including two commercial kits, and assessed intrafish variability in the distribution of K. septempunctata spores in flounder using this QPCR method in order to establish a more accurate quantitative measurement. Our QPCR assay displayed high sensitivity, specificity, and reproducibility, and had good correlation with a microscopic detection method. Our data also indicated that the DNeasy? Blood & Tissue Kit was more efficient method for the extraction of K. septempunctata DNA than the three other methods (heating, alkaline lysis, and FastDNA? SPIN Kit method). We believe that our method would be useful for investigating foodborne outbreaks caused by K. septempunctata and for the monitoring and quantification of this parasite in retail or aquacultured olive flounders to prevent such outbreaks. 相似文献
487.
Yoza B Arakaki A Maruyama K Takeyama H Matsunaga T 《Journal of Bioscience and Bioengineering》2003,95(1):21-26
Bacterial and artificial magnetic particles were modified using a polyamidoamine (PAMAM) dendrimer and outer shell amines determined. Bacterial magnetic particles were the most consistently modified. Transmission electron microscopic (TEM) analysis showed that the artificial magnetic particles were structurally damaged by the modification process including sonication. Furthermore, laser particle analysis of the magnetite also revealed damage. Small quantities of dendrimer-modified bacterial magnetic particles were used to extract DNA from blood. The efficiency of DNA recovery was consistently about 30 ng of DNA using 2-10 microg of dendrimer-modified bacterial magnetite. This technique was fully automated using newly developed liquid handling robots and bacterial magnetic particles. 相似文献
488.
N Niitsu S Iki K Muroi S Motomura M Murakami H Takeyama A Ohsaka A Urabe 《Canadian Metallurgical Quarterly》1997,76(12):1661-1666
Twenty cases of interstitial pneumonia secondary to treatment with granulocyte colony-stimulating factor (G-CSF) were reviewed. Their interstitial pneumonia had the following features: (a) it occurred predominantly in patients aged 60 years or older; (b) it was prevalent among patients with haematological malignancies, particularly non-Hodgkin's lymphoma; (c) in all patients G-CSF was given after anti-cancer agents with potential to affect the lungs; (d) at the onset, many patients had symptoms such as dyspnoea and fever; and (e) the leucocyte (neutrophil) count as well as lactate dehydrogenase (LDH) and C-reactive protein (CRP) levels were usually higher than normal at the onset. These findings indicate that, when G-CSF is used in combination with pneumotoxic anti-cancer agents, respiratory function should be monitored before and during treatment. If the leucocyte (or neutrophil) count and/or LDH and CRP increase suddenly in association with dyspnoea and fever during administration of G-CSF, interstitial pneumonia should be suspected. Accordingly, a chest radiograph and pulmonary functional tests should be performed promptly. If a diagnosis of interstitial pneumonia is made, steroid pulse therapy should be commenced immediately. 相似文献
489.
Yuko Kono Takeoka M. Uto K. Uchida A. Kannari F. 《Quantum Electronics, IEEE Journal of》2000,36(5):607-614
Lateral mode coupling in a diode-pumped Nd:YAG microchip laser array is demonstrated with a Talbot cavity for the first time. The relatively low laser gains of solid-state lasers compared with diode lasers and CO2 lasers, to which the Talbot cavity has already been applied successfully, are solved by employing a novel auxiliary Talbot cavity configuration. A brighter twin-peak far-field pattern indicating an out-of-phase array mode, whose spot is 9.3 times smaller than that obtained by incoherent superposition of the individual microchip laser outputs, is obtained from the phase-locked microchip laser array with a mode-selecting slit. Without the mode-selecting slit, a far-field pattern with a single narrow peak is obtained, showing that the array is locked in an in-phase mode, presumably because of multiple reflections in the auxiliary Talbot cavity 相似文献
490.
Summary Segmented polyether urethane (SEU) and urethaneurea (SEUU) were synthesized using ABA type triblock copolymer as a prepolymer, where A stands for poly(oxyethylene) and B stands for poly(oxytetramethylene). Lithium perchlorate was dissolved in SEU or SEUU to prepare LiC104 complexes (SEU/LiC104 and SEUU/LiC104) in film form. The highest conductivities observed here were 5.13x10-6 S cm-1 at 30°C and 3.34x10-5 S cm-1 at 50°C for LiC104/SEUU (oxyethylene-units content, 31 mol%). The ionic conductivity of these complexes was found to show the Arrhenius type temperature dependency. The effect of lithium perchlorate dissolution on the morphology of SEU and SEUU were also discussed. 相似文献