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61.
Diamond-Blackfan anaemia (DBA) is a red blood cell aplasia that in the majority of cases is associated with ribosomal protein (RP) aberrations. However, the mechanism by which this disorder leads to such a specific phenotype remains unclear. Even more elusive is the reason why non-specific agents such as glucocorticosteroids (GCs), also known as glucocorticoids, are an effective therapy for DBA. In this review, we (1) explore why GCs are successful in DBA treatment, (2) discuss the effect of GCs on erythropoiesis, and (3) summarise the GC impact on crucial pathways deregulated in DBA. Furthermore, we show that GCs do not regulate DBA erythropoiesis via a single mechanism but more likely via several interdependent pathways.  相似文献   
62.
Monolith reactors are widely considered as an alternative to the conventional trickle bed reactor. For the commercial deployment of monolith reactors, comparative performance studies are required. Reliable comparative and performance studies require a detailed understanding of the effect of phase distribution/maldistribution on the performance studies. In this work, performance and comparative studies were carried out in a relatively large column that was 4.8 cm in diameter. Experiments were performed in the same conditions that were used in studies for which phase distribution data were available. Since the properties of the catalyst used were different in both the reactors, the apparent kinetics were studied to facilitate the comparison. The hydrogenation of alpha-methyl styrene (AMS) was used as a test reaction. From the performance studies, it was found that the effect of maldistribution on the performance was stronger than the catalyst availability. From the comparative studies, it was found that the monolith reactor with maldistributed flow conditions provides higher productivity than the trickle bed reactor.  相似文献   
63.
A total of 20 weaned rabbits (33 days old) (10 per treatment) were fed one of two diets that included 150 g of sunflower meal (SF)/kg of diet or 120 g of whole white lupin (WL)/kg of diet for 42 days. The WL diet contained less saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA) but more monounsaturated fatty acids (MUFA) than the SF diet. The WL diet significantly decreased SFA and PUFA content, as well as the PUFA n − 6/PUFA n − 3 ratio and saturation, atherogenic and thrombogenic indexes in hind leg meat. The fatty acid composition in perirenal fat was similar to that of hind leg meat; however, significantly higher MUFA levels were observed in rabbits fed the WL diet. Thus, feeding rabbits the WL diet affected the fatty acid profile of hind leg meat and perirenal fat in a favourable manner.  相似文献   
64.
In 2008–2009 the total set of 237 samples of malting barley, malt, hop, wort, and beer was analysed for ochratoxin A (OTA) contamination using the ultra performance liquid chromatography (UPLC) coupled to fluorescence detection (FLD). The UPLC method is a fast technique with low limits of detection and quantification (LOD and LOQ) compared to other methods used routinely. LOD and LOQ values were 0.0003 and 0.001 ng/ml for beer, 0.05 and 0.2 μg/kg for barley and malt, 0.16 and 0.5 μg/kg for hop, respectively.  相似文献   
65.
Two types of dry fermented sausage differing in spicing mixture and the diameter (low content of red pepper + diameter 80 mm, H-sausage; high content of red pepper + diameter 55 mm, P-sausage, respectively) were produced in parallel with two different starter cultures (Pediococcus pentosaceus + Staphylococcus carnosus, B-samples and S. carnosus + Staphylococcus xylosus + Lactobacillus farciminis, F-samples, respectively). The sausages were ripened 21 days and subsequently stored 91 days at the room temperature. Concentration of both most abundant amines, putrescine and tyramine (y; mg/kg DM) increased significantly (P<0.01) in HB-sausage during ripening (x; days): y=2.5+18.13x−0.3144x2 (R2=0.99) and y=0.7+8.17x−0.1130x2 (R2=0.99), and also during storage: y=127.3+5.123x (R2=0.79) and y=26.0+3.211x (R2=0.74), respectively. At the end of ripening, putrescine (247 mg/kg DM) and tyramine (123 mg/kg DM) content in the HB-sausage was higher (P<0.05) than in the PB-sausage (12 and 9 mg/kg DM, respectively), concentration of either of these amines was negligible (1 mg/kg DM) in either type of F-inoculated sausage. Both starter culture and sausage type influenced significantly (P<0.001) both putrescine and tyramine content in the sausage; starter accounted for 57% and 55% of total variability in putrescine and tyramine content, respectively. Due to the significant (P<0.05) increase of total aerobic counts in the HB-sausage between the end of ripening and the 7th day of storage, followed by the significant (P<0.01) increase of the sum of total biogenic amines between the end of ripening (425 mg/kg DM) and the end of storage (1029 mg/kg DM), the storage of the dry fermented sausages at the room temperature should not be recommended.  相似文献   
66.
The dynamic mechanical behaviour of random copolymers of LC monomer-1-(hexyloxycarbonyl)ethyl 4-[4-(methacryloyloxy)benzoyloxy]benzoate (HB) and octyl methacrylate (OMA) was studied in the main transition and flow regions. Even though the aliphatic end groups of the side chain of HB and OMA are roughly the same, the T g temperature of poly(HB) is ∼ 80 K higher than that of poly(OMA); this fact is due to the presence of the stiff phenyl benzoate mesogenic group in the side chain of HB. With increasing content of OMA in the copolymer the superimposed curves of the storage G′ p and loss G′′ p moduli at a constant temperature shift towards shorter frequencies. It has been shown that this shift is mainly due to an increase of the free volume in the copolymers with increasing content of OMA. While HB monomer shows liquid crystalline (LC) properties, its polymer (poly(HB)) and random copolymers with OMA show only isotropic thermal behaviour because no flexible spacer is present in the side chain of HB which would decouple the main chain and mesogenic group motions. This means that neither the homopolymer of HB, nor its copolymers with a flexible comonomer retain the LC properties of the starting LC monomer, HB. Received: 26 September 1996/Revised: 7 November 1996/Accepted: 7 November 1996  相似文献   
67.
The objective of this paper concerns reduction of zinc metal content in organic coatings while preserving their high anticorrosive efficiency. The two goals can be achieved by using amorphous chalcogenides as components of the protective coating. Special attention was paid to materials containing Ge20Se80, Ge30Se70 and Ge40Se60, which were characterized by physico-chemical properties. An epoxy ester resin was used as binder for the investigated organic coatings. Organic coatings were prepared by combining zinc metal with amorphous chalcogenides. The resistance of the prepared films was evaluated using the results of mechanical tests. The anticorrosive efficiency of the prepared films was evaluated using the results of direct corrosion tests. Thus the following conclusion can be made from the results of anti-corrosive tests: the higher the pigment volume concentration of amorphous chalcogenides in the coatings, the higher the protective performance of the paint against corrosion.  相似文献   
68.
Male Colletes cunicularius bees pollinate the orchid, Ophrys exaltata, after being sexually deceived by the orchid’s odor-mimicry of the female bee’s sex pheromone. We detected biologically active volatiles of C. cunicularius by using gas chromatographic–electroantennographic detection (GC-EAD) with simultaneous flame ionization detection. After identification of the target compounds by coupled gas chromatography–mass spectrometry (GC-MS), we performed behavioral tests using synthetic blends of the active components. We detected 22 EAD active compounds in cuticular extracts of C. cunicularius females. Blends of straight chain, odd-numbered alkanes and (Z)-7-alkenes with 21–29 carbon atoms constituted the major biologically active compounds. Alkenes were the key compounds releasing mating behavior, especially those with (Z)-7 unsaturation. Comparison of patterns of bee volatiles with those of O. exaltata subsp. archipelagi revealed that all EAD-active compounds were also found in extracts of orchid labella. Previous studies of the mating behavior in C. cunicularius showed linalool to be an important attractant for patrolling males. We confirmed this with synthetic linalool but found that it rarely elicited copulatory behavior, in accordance with previous studies. A blend of active cuticular compounds with linalool elicited both attraction and copulation behavior in patrolling males. Thus, linalool appears to function as a long-range attractant, whereas cuticular hydrocarbons are necessary for inducing short-range mating behavior.  相似文献   
69.
Collomb M  Sieber R  Bütikofer U 《Lipids》2004,39(4):355-364
The concentrations of CLA isomers were determined by Ag+-HPLC in the milk fat of cows fed a control diet consisting of hay ad libitum and 15 kg of fodder beets or this diet supplemented with oilseeds containing either high levels of oleic acid (rapeseed), linoleic acid (sunflower seed), or α-linolenic acid (linseed). Highly significant (P≤0.001) correlations were found between the daily intakes of oleic acid and the concentration of the CLA isomer trans-7,cis-9 in milk fat; of linoleic acid and the CLA isomers trans-10,trans-12, trans-9,trans-11, trans-8,trans-10, trans-7,trans-9, trans-10,cis-12, cis-9,trans-11, trans-8,cis-10, and trans-7,cis-9; and of α-linolenic acid and the CLA isomers trans-12,trans-14, trans-11,trans-13, cis,trans/trans,cis-12,14, trans-11,cis-13, and cis-11,trans-13. CLA concentrations were also determined in the milk fat of cows grazing in the lowlands (600–650 m), the mountains (900–1210 m), and the highlands (1275–2120 m). The concentrations of many isomers were highest in milk fat from the highlands, but only three CLA isomers (cis-9,trans-11, trans-11,cis-13, and trans-8,cis-10) showed a nearly linear increase with elevation. Therefore, these three CLA isomers, and particularly the CLA isomer trans-11,cis-13, the second-most important CLA in milk fat from cows grazing at the three altitudes, could be useful indicators of milk products of Alpine origin.  相似文献   
70.
With increasingly strict automotive emission regulations the exhaust gas aftertreatment becomes more complex and expensive. Mathematical modelling and simulations play an important role in design of the aftertreatment systems consisting of multiple catalytic devices, reducing the time and cost demands of the system design. In this paper a combined exhaust gas aftertreatment system for diesel engines is studied. It consists of a diesel oxidation catalyst (DOC) for CO and hydrocarbons oxidation, a catalyzed diesel particulate filter (CDPF) for soot filtration, and an NOx storage and reduction catalyst (NSRC, also called lean NOx trap, LNT) for NOx abatement. Effective mathematical models of the individual converters are presented and used first to demonstrate the functionalities of the system, and then to conduct a parametric simulation study. The aim of this study is to map the influence of the individual components on the performance of the entire system in standard test driving cycle. The sizes of the DOC, CDPF, and NSRC converters are varied while the overall volume of the combined system is kept constant. The resulting maps of pressure drop, CO, HC, particulate matter, and NOx conversions show non-linear dependences on the sizes of individual converters. Co-operative and competitive effects occurring in the combined system are discussed. Suitable reactors sizes are found that enable high conversions of all controlled exhaust gas components.  相似文献   
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