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91.
Confined goats spend a substantial part of the day feeding. A poorly designed feeding place increases the risk of feeding in nonphysiological body postures, and even injury. Scientifically validated information on suitable dimensions of feeding places for loose-housed goats is almost absent from the literature. The aim of the present study was, therefore, to determine feeding place dimensions that would allow goats to feed in a species-appropriate, relaxed body posture. A total of 27 goats with a height at the withers of 62 to 80 cm were included in the study. Goats were tested individually in an experimental feeding stall that allowed the height difference between the feed table, the standing area of the forelegs, and a feeding area step (difference in height between forelegs and hind legs) to be varied. The goats accessed the feed table via a palisade feeding barrier. The feed table was equipped with recesses at varying distances to the feeding barrier (5–55 cm in 5-cm steps) at angles of 30°, 60°, 90°, 120°, or 150° (feeding angle), which were filled with the goats' preferred food. In 18 trials, balanced for order across animals, each animal underwent all possible combinations of feeding area step (3 levels: 0, 10, and 20 cm) and of difference in height between feed table and standing area of forelegs (6 levels: 0, 5, 10, 15, 20, and 25 cm). The minimum and maximum reach at which the animals could reach feed on the table with a relaxed body posture was determined for each combination. Statistical analysis was performed using mixed-effects models. The animals were able to feed with a relaxed posture when the feed table was at least 10 cm higher than the standing height of the goats' forelegs. Larger goats achieved smaller minimum reaches and minimum reach increased if the goats' head and neck were angled. Maximum reach increased with increasing height at withers and height of the feed table. The presence of a feeding area step had no influence on minimum and maximum reach. Based on these results, the goats' feeding place can be designed to ensure that the animals are able to reach all of the feed in the manger or on the feed table with a relaxed posture, thus avoiding injuries and nonphysiological stress on joints and hooves. A feeding area step up to a maximum of 20 cm need not be taken into account in terms of feeding reach. However, the feed table must be raised at least 10 cm above the standing area to allow the goats to feed in a species-appropriate, relaxed posture.  相似文献   
92.
Au-Sn solid–liquid interdiffusion (SLID) bonding is an established reliable high temperature (HT) die attach and interconnect technology. This article presents the life cycle of an optimized HT Au-Sn SLID bond, from fabrication, via thermal treatment, to mechanical rupture. The layered structure of a strong and uniform virgin bond was identified by X-ray diffraction to be Au/ζ (Au0.85Sn0.15)/Au. During HT exposure, it was transformed to Au/β (Au1.8Sn0.2)/Au. After HT exposure, the die shear strength was reduced by 50 pct, from 14 Pa to 70 MPa, which is still remarkably high. Fractographic studies revealed a change in fracture mode; it was changed from a combination of adhesive Au/Ni and cohesive SiC fracture to a cohesive β-phase fracture. Design rules for high quality Au-Sn SLID bonds are given.  相似文献   
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94.
High-pressure-processing (HPP) at 400 or 600 MPa was applied to cheeses made from ewe raw milk, on days 21 or 35 after manufacturing, to reduce proteolysis and prevent over-ripening. The characteristics of HPP and non-pressurized (control) cheeses were compared during ripening at 8 °C until day 60 and further storage at 4 °C until day 240. HPP and control cheeses showed similar pH values throughout ripening, but on day 240 pH values remained 0.4–0.6 units lower for HPP cheeses than for the control cheeses. Casein degradation was significantly retarded in the 600 MPa cheeses. Their α-casein concentration was 48–52 % higher on day 60 and 30–33 % higher on day 240 than in the control cheeses while β-casein concentration was 25–26 % higher on day 60 and 100–103 % higher on day 240. No significant differences in para-κ-casein concentration between cheeses were found on day 60, but on day 240, it was 22–35 % higher in the 600 MPa cheeses than in the control cheese. Hydrophilic peptides, hydrophobic peptides and total free amino acids evolved similarly in HPP and control cheeses during the 60-day ripening period. However, on day 240 hydrophilic peptides were at 34–39 % lower levels in the 600 MPa cheeses than in the control cheeses, hydrophobic peptides at 7–16 % lower levels and total free amino acids at 25–29 % lower levels. Flavour intensity scores increased at a slower rate in HPP cheeses than in the control cheese. Flavour quality declined markedly in the control cheeses during refrigerated storage while it did not vary significantly in 600 MPa cheeses.  相似文献   
95.
Phenolic compounds were determined in artichoke (Cynara scolymus), garlic (Allium sativium) and spinach (Spinacia oleracea) using a single method based on simple extraction and ultra-high-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). Several compounds belonging to different families, such as phenolic acids, isoflavones, flavones and flavonols, were determined. The analytical procedure was validated in all the matrices, obtaining recoveries ranging from 60 to 120 % with reproducibility values (expressed as relative standard deviations (RSDs)) lower than 26 %. Limits of quantification (LOQs) were always equal to or lower than 50 μg/kg, except to kaempferol and its glucosides in spinach (LOQs?=?75 μg/kg). Artichoke showed higher concentration of phenolic compounds (837.2 mg/kg dry weight (DW)) than garlic (26.5 mg/kg DW) or spinach (64.5 mg/kg DW). Apigenin 7-O-glucoside (from 147.0 to 722.7 mg/kg DW) was found to be the major flavonoid in all samples of artichoke investigated, while chlorogenic acid, whose concentration ranged from 37.8 to 734.7 mg/kg DW, is the major phenolic acid in this matrix. Regarding garlic, caffeic acid (from 1.7 to 28.3 mg/kg DW) and quercetin (from 9.0 to 18.9 mg/kg DW) were the compounds detected at higher concentrations, although in general the total content was very low in relation to other matrices. In relation to spinach, ferulic acid was the major phenolic compound, and its concentration ranged from 18.0 to 41.4 mg/kg DW.  相似文献   
96.
97.
Several lines of evidence point to olive oil and the olive oil-centered Mediterranean diet as conducive to longevity. The evidence stems from ecological, as well as analytic epidemiological studies assessing olive oil, monounsaturated lipids or the Mediterranean dietary pattern in relation to the incidence of, or mortality from, major common diseases, or overall mortality. Mechanistic considerations are addressed by biochemical studies, whereas randomized clinical trials provide further support to the evidence generated from observational investigations. The content of olive oil in several microcomponents with antioxidant potential, as well as its high content in monounsaturated lipids appear to be essential for the beneficial effect of this food.  相似文献   
98.
This work describes the effects of freezing preservation on mango (cvs Lippens and Smith) peroxidase (E.C. 1.11.1.7); POD). Frozen mango slices showed lower levels of POD activity than raw fruits (17% cv Lippens; 50% cv Smith after 2 months storage time). A regeneration of this activity was found after 6 months of frozen storage. Regeneration continued to the end of the study (12 months) in both cultivars. During the whole period of storage, inactivation rates in Smith POD were higher than in Lippens. The isoenzymic pattern of Lippens POD showed four strongly anionic species that did not appear in the Smith pattern. The activity of these four bands is the most stable to low temperatures, and is the possible cause of the major resistence of Lippens peroxidase to freezing and frozen storage. Thus the Smith cultivar may be more suitable for freezing preservation.
Einfluß der Gefrierlagerung auf die Aktivität der Mangoperoxidase (Mangifera indica, L.)
Zusammenfassung Diese Arbeit beschreibt die Auswirkungen der Gefrierlagerung auf die Peroxidase (E.C. 1.11.1.7) von Mangofrüchten, Sorte Lippens und Smith. Die gefrorenen Mangoscheiben wiesen niedrigere Peroxidasewerte auf als die rohen Früchte (um 17% geringer bei Lippens und um 50% bei Smith, nach zwei Monaten Lagerung). Eine Reaktivierung konnte nach sechs Monaten Tiefkühlung festgestellt werden. Diese Reaktivierung hielt bei beiden Mangosorten bis zum Ende der Untersuchung (also 12 Monate) an. Während der ganzen Lagerungszeit ließ die Inaktivierung der Peroxidase der Lippens vier stark anionische Formen erkennen, die bei der Sorte Smith nicht auftraten. Es stellte sich heraus, daß die Aktivität dieser vier Formen die größte Stabilität gegenüber tiefen Temperaturen aufweist. Wahrscheinlich ist das der Grund für die größere Widerstandsfähigkeit der Peroxidase der Sorte Lippens gegenüber Gefrieren und Tiefkühlung. Dieses Ergebnis weist auf eine bessere Eignung für die Gefrierkonservierung der Mangosorte Smith hin.
  相似文献   
99.
Many studies have shown that the presence of 1,25-dihydroxyvitamin D3 in the eye is able to modulate inflammatory responses. In fact, it has been demonstrated that topical administration of vitamin D3 inhibits Langerhans cells migration from the central cornea, corneal neovascularization, and production of cytokines (i.e., interleukin-1-6-8) in experimental animals.

Moreover, both in vitro and in vivo studies have demonstrated that vitamin D is a potent inhibitor of retinal neovascularization. It has been shown that calcitriol, the biologically active form of vitamin D, inhibits angiogenesis both in cultured endothelial cells and in retinas from guinea pigs with retinoblastoma or oxygen-induced ischemic retinopathy. In addition, it seems that this compound is able to prevent the progression from early to neovascular age-related macular degeneration (AMD) and, at the same time, to down-regulate the characteristic inflammatory cascade at the retinal pigment epithelium–choroid interface due to its anti-inflammatory and immunomodulatory capabilities.

Furthermore, 1,25-dihydroxyvitamin D3 and its analogue, 2-methylene-19-nor-1,25-dihydroxyvitamin D3, are able to modulate intraocular pressure (IOP) through gene expression. Several studies have suggested a role in glaucoma and diabetic retinopathy therapies for vitamin D3.

In conclusion, this review summarizes our current knowledge on the potential use of vitamin D3 in the protection and treatment of ocular diseases in ophthalmology.  相似文献   

100.
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