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291.
292.
Propylene oxide (PPO) is commonly used to reduce microbial populations in U.S. bulk raw almonds, but the process has not been validated for reduction of foodborne pathogens. The reduction of Salmonella Enteritidis phage type (PT) 30 inoculated onto almonds was evaluated after exposure to a standard commercial PPO treatment. Almonds were inoculated with Salmonella Enteritidis PT 30 to approximately 8.0 log CFU/g after drying. Inoculated almonds were placed in bags designed for gaseous sterilization and positioned in the center of 900-kg bins or 22.7-kg boxes of warmed almonds. Almonds were further warmed to an initial temperature of 23 to 34 degrees C, treated with PPO (0.5 kg/m3 for 4 h), and held for 0 or 2 days at 38 to 43 degrees C followed by storage for 2 to 5 days at 15 to 18 degrees C. Salmonella Enteritidis PT 30 was recovered by vigorously shaking 100 g of almonds in 100 ml of Butterfield's phosphate buffer, plating onto tryptic soy or bismuth sulfite agar, and incubating at 35 degrees C for 24 or 48 h, respectively. Populations of Salmonella Enteritidis were consistently reduced by > 5.0 log CFU/g (5.2 to > 8.6 log CFU/ g) when initial counts were compared with counts obtained 5 days after PPO treatment. Reductions of 1.2 to 4.4 log CFU/g occurred during post-PPO storage. Reductions were not significantly improved (P < 0.05) when almonds were held at 38 to 43 degrees C after PPO treatment. PPO residues were > 400 ppm immediately after removal from the PPO chamber and declined to < 300 ppm during post-PPO storage. PPO is an effective treatment for reducing populations of Salmonella Enteritidis PT 30 on bulk almonds.  相似文献   
293.
We have successfully prepared thin films of PbBr-based layered perovskite having hole-transporting carbazole chromophore-linked ammonium molecules as an organic layer by a simple spin-coating from the N,N-dimethylformamide solution in which the stoichiometric amount of lead bromide and carbazole-linked ammonium bromides was dissolved. Their X-ray diffraction profiles exhibited that their layer structure formed (0 0 n)-orientation, where c-axis is perpendicular to the substrate plane. Their layer structure depended on the alkyl chain length of ammonium molecules. When methylene length of C5H10 was employed in the carbazole-linked ammonium molecules, highest orderliness of the layer structure was attained; higher-order X-ray diffraction peaks were observed in the layered perovskite films. In the layered pervskite film, in-plane conduction, namely conduction in the direction of the stacking of carbazole chromophore, was measured. For comparison, conductivity of poly(N-vinylcarbazole) (PVCBz) thin film was also measured. The conductivity of the layered perovskite thin film (1.8 × 10?10 Scm?1 at 303 K) was about three order of magnitude larger than that of the PVCBz thin film (5.3 × 10?14 Scm?1 at 303 K). Despite the much higher conductivity of the layered peroskite thin film, the activation energy of the conductivity of the layered perovskite thin film (1.44 eV) was about 2.4 times larger than that of the PVCBz thin film (0.61 eV). This phenomenon is probably due to difference in film morphology through considering the results of AFM observation.  相似文献   
294.
Background: Hepatocyte growth factor (HGF) is an endogenously induced bioactive molecule that has strong anti-apoptotic and tissue repair activities. In this research, we identified APOA4 as a novel pharmacodynamic (PD) marker of the recombinant human HGF (rh-HGF), E3112. Methods: rh-HGF was administered to mice, and their livers were investigated for the PD marker. Candidates were identified from soluble proteins and validated by using human hepatocytes in vitro and an animal disease model in vivo, in which its c-Met dependency was also ensured. Results: Among the genes induced or highly enhanced after rh-HGF exposure in vivo, a soluble apolipoprotein, Apoa4, was found to be induced by rh-HGF in the murine liver. By using primary cultured human hepatocytes, the significant induction of human APOA4 was observed at the mRNA and protein levels, and it was inhibited in the presence of a c-Met inhibitor. Although mice constitutively expressed Apoa4 mRNA in the small intestine and the liver, the liver was the primary organ affected by administered rh-HGF to strongly induce APOA4 in a dose- and c-Met-dependent manner. Serum APOA4 levels were increased after rh-HGF administration, not only in normal mice but also in anti-Fas-induced murine acute liver failure (ALF), which confirmed the pharmacodynamic nature of APOA4. Conclusions: APOA4 was identified as a soluble PD marker of rh-HGF with c-Met dependency. It should be worthwhile to clinically validate its utility through clinical trials with healthy subjects and ALF patients.  相似文献   
295.
Dynamic microfluidic gelation enables the fabrication of bundle-structured multiple parallel microgel filaments from an aqueous two-phase system. The formation mechanism of shear-induced filaments from an alginate (Alg)/polyvinyl alcohol (PVA) blend is studied using red-colored PVA and a titanium alkoxide PVA crosslinker. Bundle-structured Alg microgel filaments are formed through contact with a Ca2+ crosslinker. In this process, the PVA acts as a sacrificial polymer to maintain the Alg gel filaments because approximately 90% of the red-colored PVA is released from the Ca2+-crosslinked Alg gel filaments into the wash water. In addition, the fabrication of PVA gel filaments shows that the sacrificial PVA is also transformed into fibrillar domains under shear. However, the filament structure cannot be formed from a single-phase PVA/Alg solution. These results clearly show that the bundle-structured gel filaments are maintained by preventing the fusion of filaments during gelation based on the tendency of the non-crosslinked filaments to cause splitting of the gelled filaments.  相似文献   
296.
297.
Syringic acid, a phenolic compound, serves a variety of beneficial functions in cells. Syringic acid increases in plants in response to cesium, and exogenous application of syringic acid resulted in a significant attenuation of cesium-induced growth defects in Arabidopsis. In addition, cesium or syringic acid application to plants also resulted in increased lignin deposition in interfascicular fibers. To better understand the role of lignin and syringic acid in attenuating cesium-induced growth defects, two mutants for Arabidopsis REDUCED EPIDERMAL FLUORESCENE 4 (REF4) and fourteen laccase mutants, some of which have lower levels of lignin, were evaluated for their response to cesium. These mutants responded differently to cesium stress, compared to control plants, and the application of syringic acid alleviated cesium-induced growth defects in the laccase mutants but not in the ref4 mutants. These findings imply that lignin plays a role in cesium signaling but the attenuation of cesium stress defects by syringic acid is mediated by regulatory components of lignin biosynthesis and not lignin biosynthesis itself. In contrast, syringic acid did not alleviate any low potassium-induced growth defects. Collectively, our findings provide the first established link between lignin and cesium stress via syringic acid in plants.  相似文献   
298.
OBJECTIVE: The traditional goal of obesity therapy has been the reduction of body weight to an ideal standard. Patient difficulties, however, in reaching this goal have led to a reassessment of weight loss criteria. The Institute of Medicine of the National Academy of Sciences recently proposed that successful long-term weight loss be defined as the reduction of initial weight by 5% or more and the maintenance of this loss for at least 1 year. The present study used these criteria to evaluate the long-term efficacy of a proprietary weight loss program. METHODS: Patients were 621 persons who had completed a 26-week weight loss program that included 12 weeks of treatment by a very-low-calorie diet. They were recruited from a total of 1,283 eligible persons who had been treated at 36 clinics nationwide. Clinics were randomly selected to participate. Patients' weights were determined in telephone interviews initially conducted 2 years after treatment and then at yearly intervals through 5 years of follow-up. RESULTS: At the end of treatment, men achieved a mean reduction in initial weight of 25.5 +/- 1% and women 22.6 +/- 1%. Subjects regained substantial amounts of weight by the 2-year follow-up but 77.5% of men and 59.9% of women still maintained losses of 5% or more of body weight. At the 3-year follow-up, 53% of the original sample (of 621 persons) maintained losses of 5% or more and 35% losses of 10% or more. These trends were apparent 4 and 5 years after treatment but the dwindling sample sizes prevented definitive assessments. DISCUSSION: The findings showed that a program of lifestyle modification combined with the brief use of a very-low-calorie diet was associated with successful weight control in a substantial portion of patients several years after treatment. Long-term weight losses of 5% or more of initial weight are likely to be associated with improvements in health complications.  相似文献   
299.
Traceback investigation of a 2000 to 2001 outbreak of salmonellosis associated with consumption of raw almonds led to isolation of the outbreak strain Salmonella enterica serovar Enteritidis phage type (PT) 30 on three geographically linked almond farms. Interviews with these growers revealed that significant rain fell during the 2000 harvest when many almonds were drying on the ground. The objectives of this study were to document weather conditions during the 2000 harvest, determine the potential for growth of Salmonella Enteritidis PT 30 in hull or shell slurries, and evaluate survival of Salmonella Enteritidis PT 30 on wet almond hulls during drying. Dry almond hulls and in-shell kernels wetted for 24 h increased in weight by 250 to 300% and 100%, respectively. Both hull and shell slurries supported rapid growth of Salmonella Enteritidis PT 30 at 24 degrees C; slurries containing hulls also supported growth at 15 degrees C. Maximum Salmonella Enteritidis PT 30 concentrations of 6.2 and 7.8 log CFU/ml were observed at 15 and 24 degrees C, respectively. Salmonella Enteritidis PT 30 grown in wet hulls that were incubated at 24 degrees C survived drying at either 15 or 37 degrees C. Reductions of 1 to 3 log CFU/g of dry hull were observed during drying; reductions generally declined as incubation time increased from 2 to 7 days. Evaluation of shipping records revealed that approximately 60% of outbreak-associated almonds had not been exposed to rain, eliminating this factor as the sole cause of the outbreak. However, the data provide evidence that wet almonds may be a greater risk for high concentrations of Salmonella, and specific guidelines should be established for harvesting and processing almonds that have been exposed to rain or other water sources.  相似文献   
300.
It has generally been assumed that metals usually fail as a result of microvoid nucleation induced by particle fracture. Here, we concentrate on high-density micropores filled with hydrogen in aluminum, existence of which has been largely overlooked until quite recently. These micropores exhibit premature growth under external loading, thereby inducing ductile fracture, whereas the particle fracture mechanism operates only incidentally. Conclusive evidence of a micropore mechanism is provided by the observation of an instantaneous release of gas at failure. We can therefore conclude that the growth of micropores dominates ductile fracture. Since the material we used has a standard pore density, we can assume that an identical fracture mechanism operates in other aluminum alloys. This finding suggests that intense heat treatment, which is generally believed to enhance the mechanical properties through homogenization, may have entirely the opposite effect. This revelation will have a major impact on the engineering design of metals.  相似文献   
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