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71.
M Garbuglia M Verzini RR Rustandi D Osterloh DJ Weber V Gerke R Donato 《Canadian Metallurgical Quarterly》1999,254(1):36-41
Controversy over the efficacy of many topical wound treatments, particularly growth factors, is common, with many clinical practitioners still confused as to the real value of these agents. A serious lack of knowledge appears to exist concerning the diffusion and distribution of topically applied solutes in wounds. Without this basic understanding there seems little chance of accurately predicting the therapeutic window of drugs targeted at cellular activities, such as division and chemotaxis, and processes, such as collagen lattice deposition and contraction, occurring below the surface of the granulating layer. This study was designed to determine the absorption and distribution of a number of radiolabeled solutes (water, sodium chloride, lidocaine) and growth factors (basic fibroblast growth factor, epidermal growth factor) applied topically to full-thickness excisional wounds in rats during the early (2 d), mid (7 d), and late (12 d) stages of repair. Results showed that water and sodium penetrated deepest into wound sites and that changes in water distribution and retention in the wound paralleled the healing process. Multiple stepwise regression showed that molecular weight and tissue depth, but not day of healing, were significant factors in predicting the concentration of each solute in wound and underlying tissue sites. This finding was consistent with a tissue diffusion model developed in this study. Basic fibroblast growth factor and epidermal growth factor only penetrated slightly into the upper granulating layers of the wound site, and calculation of therapeutic doses, based on the percentage of applied solute reaching the deeper granulating layers, is presented. 相似文献
72.
Carlo Bonini Maurizio D'Auria Giacomo Mauriello Rachele Pucciariello Roberto Teghil Daniela Tofani Licia Viggiani Donato Viggiano Francesco Zimbardi 《应用聚合物科学杂志》2001,79(1):72-79
The synthesis of copolymers between lignin from steam‐exploded straw and 1‐ethenylbenzene is described. Beforehand, lignin from steam‐exploded straw was fully characterized by using elemental analysis, ultraviolet spectroscopy, gel permeation chromatography (GPC), Fourier transform infrared (FTIR), and both 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. Using a previously described procedure utilizing calcium chloride and hydrogen peroxide as reagents the synthesis of the copolymers was performed. FTIR of the copolymers showed the presence of both lignin and polystyrene. GPC analysis showed the presence of a fraction with high molecular weights. These results were confirmed from both viscosity data and differential calorimetry. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 72–79, 2001 相似文献
73.
Vanadium pentoxide (V2O5) nanocrystals having few tens nanometers average size, are obtained from ammonium metavanadate (NH4VO3) in the presence of oleic acid, and treating the reaction product at 400 °C. Nanocrystalline films, deposited from stable ethanol suspensions of the V2O5 nanopowder, adhere strongly to different kinds of substrates, without the need of any thermal post processing. At room temperature, the films are found to bleach when exposed to ammonia. Bleaching originates from the formation of ammonium metavandate, and is reversible, as after annealing in air at 350 °C, ammonium metavanadate converts back to V2O5. Formation of ammonium metavanadate, clearly evidenced by remarkable changes in infrared spectrum of V2O5 films exposed to ammonia, is a valuable detection mechanism, promising in view of developing highly selective ammonia sensors operating at room temperature. 相似文献
74.
A stable chlorobenzene dispersion of conducting polyaniline (PANI) has been obtained by doping emeraldine base with dodecylbenzene sulfonic acid (DBSA) and studied by spectrophotometric measurements in the UV-vis-IR range. The electrical properties of PANI: DBSA films obtained from the above dispersion have been investigated under different temperature and relative humidity conditions. All-organic chemoresistive devices have been developed by spin-coating the PANI: DBSA dispersion on flexible substrates, and then by depositing electrodes on the top, from a carbon nanotube conducting ink. Sensing tests performed under exposition to calibrated amounts of ammonia reveal that these simple and inexpensive sensors are able to detect ammonia at room temperature in a reliable way, with a sensitivity linearly related to concentration in the range between 5 ppm and 70 ppm. 相似文献
75.
Maura N. Laus Anna Gagliardi Mario Soccio Zina Flagella Donato Pastore 《Journal of food science》2012,77(11):C1150-C1155
Abstract: Antioxidant activity (AA) of quinoa (Chenopodium quinoa Willd.) seeds, as well as of durum wheat (Triticum turgidum L. ssp. durum Desf.) and of emmer (T. turgidum L. ssp. dicoccum Schübler) grains, was evaluated by studying hydrophilic (H), lipophilic (L), free‐soluble (FSP) and insoluble‐bound (IBP) phenolic extracts using the new lipoxygenase/4‐nitroso‐N,N‐dimethylaniline (LOX/RNO) method, able to simultaneously detect different antioxidant mechanisms, as well as using the Oxygen Radical Absorbance Capacity (ORAC) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays, which measure the scavenging activity against peroxyl and ABTS [2,2′‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonate)] radicals, respectively. The species under study were compared with respect to the sum of AA values of H, L and FSP extracts (AAH+L+FSP), containing freely solvent‐soluble antioxidants, and AA values of IBP extracts (AAIBP), representing the phenolic fraction ester‐linked to insoluble cell wall polymers. The LOX/RNO and ORAC methods measured in quinoa flour a remarkable AAH+L+FSP higher than durum wheat, although lower than emmer; according to the same assays, the IBP component of quinoa resulted less active than the durum wheat and emmer ones. The TEAC protocol also revealed a high AAH+L+FSP for quinoa. Interestingly, the ratio AAH+L+FSP/AAH+L+FSP+IBP, as evaluated by the LOX/RNO and ORAC assays, resulted in quinoa higher than that of both durum wheat and emmer, and much higher than durum wheat, according to the TEAC protocol. This may suggest that antioxidants from quinoa seeds may be more readily accessible with respect to that of both the examined wheat species. Practical Applications: Quinoa seeds may represent an excellent source of natural antioxidant compounds and, in particular, of the free‐soluble antioxidant fraction. These compounds may improve nutritive and health‐beneficial properties of quinoa‐based gluten‐free products, thus expanding interest for quinoa utilization from celiac patients to the general population. 相似文献
76.
Paraboschi EM Soldà G Gemmati D Orioli E Zeri G Benedetti MD Salviati A Barizzone N Leone M Duga S Asselta R 《International journal of molecular sciences》2011,12(12):8695-8712
Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system characterized by chronic inflammation, demyelination, and axonal damage. As microRNA (miRNA)-dependent alterations in gene expression in hematopoietic cells are critical for mounting an appropriate immune response, miRNA deregulation may result in defects in immune tolerance. In this frame, we sought to explore the possible involvement of miRNAs in MS pathogenesis by monitoring the differential expression of 22 immunity-related miRNAs in peripheral blood mononuclear cells of MS patients and healthy controls, by using a microbead-based technology. Three miRNAs resulted >2 folds up-regulated in MS vs controls, whereas none resulted down-regulated. Interestingly, the most up-regulated miRNA (mir-155; fold change = 3.30; P = 0.013) was previously reported to be up-regulated also in MS brain lesions. Mir-155 up-regulation was confirmed by qPCR experiments. The role of mir-155 in MS susceptibility was also investigated by genotyping four single nucleotide polymorphisms (SNPs) mapping in the mir-155 genomic region. A haplotype of three SNPs, corresponding to a 12-kb region encompassing the last exon of BIC (the B-cell Integration Cluster non-coding RNA, from which mir-155 is processed), resulted associated with the disease status (P = 0.035; OR = 1.36, 95% CI = 1.05-1.77), suggesting that this locus strongly deserves further investigations. 相似文献
77.
Seung‐Ho Yu Donato E. Conte Seunghwan Baek Dong‐Chan Lee Seung‐Keun Park Kyung Jae Lee Yuanzhe Piao Yung‐Eun Sung Nicola Pinna 《Advanced functional materials》2013,23(35):4293-4305
Non‐aqueous sol‐gel routes involving the reaction of metal oxide precursors in organic solvents (e.g., benzyl alcohol) at moderate temperature and pressure, offer advantages such as high purity, high reproducibility and the ability to control the crystal growth without the need of using additional ligands. In this paper, a study carried out on a series of iron oxide/reduced graphene oxide composites is presented to elucidate a structure‐properties relationship leading to an improved electrochemical performance of such composites. Moreover, it is demonstrated that the easy production of the composites in a variety of temperature and composition ranges, allows a fine control over the final particles size, density and distribution. The materials obtained are remarkable in terms of the particle's size homogeneity and dispersion onto the reduced graphene oxide surface. Moreover, the synthesis method used to obtain the graphene oxide clearly affects the performances of the final composites through the control of the restacking of the reduced graphene oxide sheets. It is shown that a homogeneous and less defective reduced graphene oxide enables good electrochemical performances even at high current densities (over 500 mAh/g delivered at current densities as high as 1600 mA/g). The electrochemical properties of improved samples reach the best compromise between specific capacity, rate capability and cycle stability reported so far. 相似文献
78.
79.
Structural and biochemical characteristics of bovine intramuscular connective tissue and beef quality 总被引:1,自引:0,他引:1
Annabelle Dubost Didier Micol Brigitte Picard Claire Lethias Donato Andueza Dominique Bauchart Anne Listrat 《Meat science》2013
The aim of the study was to evaluate the impact of structural and biochemical characteristics of muscle intramuscular connective tissue on beef quality. The experimental design was based on three muscles of three breeds sampled as fresh material and cooked at 55 °C (Longissimus thoracis and Semimembranosus) or at 70 °C (Semimembranosus and Biceps femoris) for quality assessment. The results showed that muscle characteristics influence beef quality differently from one muscle to another. In grilled LT, proteoglycan content contributed negatively to juiciness, and intramuscular lipids were linked positively to tenderness, flavour, residues and overall liking scores. In grilled SM, cross-link and lipid contents were involved in beef quality. In BF cooked to 70 °C, perimysial branch points were negatively linked to tenderness. In SM cooked to 70 °C, perimysial area was involved in beef quality. These results should allow a better understanding of the factors involved in background toughness, in juiciness and flavour of meat. 相似文献
80.