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581.
The qualitative characteristics, lipids and chemical composition of the meat of 35 Nellore young bulls were analyzed. These bulls had an average slaughter weight and fat thickness of 532.17 ± 30.2 kg, and 7.00 mm, respectively. Significant differences were found only in the meat's water holding capacity (WHC), which was higher for animals fed with fresh linseed oil. More conjugated linoleic acid (CLA) was found in the meat of animals fed with unprotected soybean oil, while better omega-6/omega-3 ratios were noted for those fed unprotected linseed oil. The addition of different vegetable oils to the bulls' diet (soybean or linseed, either protected or not protected from rumen digestion) did not interfere with the qualitative characteristics of their meat while improving the lipid composition of the longissimus muscle. Of the oils examined, unprotected linseed oil most improved the omega-6/omega-3 ratio, thus producing the healthiest meat for human consumption.  相似文献   
582.
Beef from retail and foodservice establishments in 11 US cities was evaluated using Warner-Bratzler shear (WBS) and consumer evaluation panels. Postmortem aging times ranged from 3 to 83d for retail and 7 to 136d for foodservice with mean aging times of 22.6d and 30.1d, respectively. For retail, the three cuts from the round - top round, bottom round, and eye of round - had the highest (P<0.05) WBS values compared to cuts from the chuck, rib, and loin. Top loin steaks had the lowest (P<0.05) WBS value compared to ribeye and top sirloin foodservice steaks. Retail bone-in top loin, top loin, ribeye, T-bone, and porterhouse received the highest (P<0.05) ratings by consumers for overall like and like tenderness. Quality grade had little or no effect on foodservice sensory evaluations. Improvements in round tenderness are needed to increase consumer acceptability.  相似文献   
583.
Characterization of the N-glycosylation present in the Fc region of therapeutic monoclonal antibodies requires rapid, high-resolution separation methods to guarantee product safety and efficacy during all stages of process development. Determination of fucosylated oligosaccharides is particularly important during clone selection, product characterization, and lot release as fucose has been shown to adversely affect the ability of mAbs to induce antibody dependent cellular cytotoxicity (ADCC). Here, we apply a general capillary electrophoresis optimization strategy to separate functionally relevant fucosylated and afucosylated glycans on mononclonal antibody products in the presence of several high mannose oligosaccharides. The N-glycans chosen represent those most commonly reported on CHO cell derived therapeutic antibodies. A rapid (<7 min) high-resolution separation of 12 commonly reported and functionally important IgG glycans was developed by systematically evaluating the effects of selectivity (boric acid) and efficiency (linear polyacrylamide) enhancing additives. The approach can be used to rapidly optimize capillary electrophoresis separation of other glycan mixtures. Following optimization, the method was applied to overnight sample processing for automated 96 well plate-based glycosylation analyses of two nonproprietary therapeutic monoclonal antibodies, demonstrating ruggedness and suitability for high-throughput process and product monitoring applications.  相似文献   
584.
Post-translational modifications, in particular glycosylation, represent critical structural attributes that govern both the pharmacodynamic and pharmacokinetic properties of therapeutic glycoproteins. To guarantee safety and efficacy of recombinant therapeutics, characterization of glycosylation present is a regulatory requirement. In the current paper, we applied a multidimensional strategy comprising a shallow anion exchange gradient in the first dimension, followed by analysis using the recently introduced 1.7 μm HILIC phase in the second dimension for the comprehensive separation of complex N-glycans present on the European Biological Reference Preparation (BRP) 3 erythropoietin standard. Tetra-antennary glycans with multiple sialic acids and poly-N-acetyl lactosamine extensions were the most abundant oligosaccharides present on the molecule. Site-specific glycan analysis was performed to examine microheterogeneity. Tetra-antennary glycans with up to four sialic acids and up to five poly-N-acetyl lactosamine extensions were observed at asparagine 24 and 83, while biantennary glycans were the major structures at asparagine 38. The combined AEC x UPLC HILIC allows for the rapid and comprehensive analysis of complex N-glycosylation present on therapeutic glycoproteins, such as BRP3 erythropoietin.  相似文献   
585.
Abstract: Sodium acid sulfate (SAS) dip treatments were evaluated against a distilled water control and citric acid (CA) to compare its effectiveness in reducing enzymatic browning of raw, French‐fry cut potatoes. Two separate studies were conducted with dip concentrations ranging from 0%, 1%, and 3% in experiment 1 to 0%, 2%, and 2.5% in experiment 2 to determine optimal dip concentrations. Russet Burbank potatoes were peeled, sliced, and dipped for 1 min and stored at 3 °C. Color, texture, fry surface pH, and microbiological analyses were conducted on days 0, 7, and 14. The 3% SAS‐ and CA‐treated samples had significantly (p < 0.0001) lower pH levels on fry surfaces than all other treatments. Both acidulants had significantly (p ≤ 0.05) lower aerobic plate counts compared to controls in both studies by day 7. However, SAS appeared to be the most effective at the 3% level in maintaining a light fry color up to day 14 and had the highest L‐values than all other treatments. The 3% SAS‐treated fry slices appeared to have the least change in textural properties over storage time, having a significantly (p = 0.0002) higher force value (kg force [kgf]) than the other treatments during experiment 1, without any signs of case‐hardening that appeared in the control and CA‐treated samples. SAS was just as comparable to CA in reducing surface fry pH and also lowering microbial counts over storage time. According to the results, SAS may be another viable acidulant to be utilized in the fresh‐cut fruit and vegetable industry.  相似文献   
586.
A low-cost single-stage laboratory process combining fungal dehydration and lipid extraction was compared with a traditional two-stage method employing freeze-drying and subsequent mechanical disruption in the presence of solvent. The ability of a number of organic solvents to form hetero-azeotropes with water was exploited. Chloroform, cyclohexane and hexane were assessed in their abilities to both dry and extract lipid from the oleaginous phycomycete Mortierella alpina (ATCC 32222). Drying rate and lipid extraction were maximised under conditions that prevented fungal agglomeration. The total processing time was limited by the rate of dehydration rather than by the rate of lipid extraction. In all cases azeotropic distillation facilitated a greater rate of dehydration than was possible with freeze-drying. A consequent reduction in overall processing time was observed. Uniquely, both the solvent used and the mode of mixing employed controlled the morphology of the aggregates formed during distillation. In combination with mild mixing chloroform discouraged agglomeration whereas cyclohexane and hexane promoted aggregation. Successful lipid extraction was dependent on the use of dry biomass rather than on the application of heat to effect distillation. Neither the application of heat nor the solvent employed had any significant effect on the lipid composition of the extracted oil.  相似文献   
587.
Cadmium adsorption on goethite-coated sand in the presence of humic acid   总被引:4,自引:0,他引:4  
Lai CH  Chen CY  Wei BL  Yeh SH 《Water research》2002,36(20):4943-4950
Heat was employed to coat crystalline goethite onto a quartz sand surface so that the adsorbent properties of the coating could be utilized. The adsorption characteristics of cadmium and humic acid onto goethite-coated sand were examined. Results show that the goethite-coated sand surface had a higher specific surface area and more mesopores than the uncoated sand. The adsorption of both cadmium and humic acid was highly pH-dependent: cadmium adsorption increased with pH, but humic acid adsorption decreased as pH increased. The presence of humic acid resulted in increasing cadmium adsorption in a specific pH range. The order of reacting humic acid with cadmium was found to have a noticeable effect on the final adsorption capacity. The adsorption capacity of cadmium for humic acid that is adsorbed onto goethite-coated sand before reacting with a cadmium system, exceeds that of humic acid that is mixed with cadmium ions before goethite-coated sand is added.  相似文献   
588.
Lin BL  Hosomi M  Murakami A 《Water research》2002,36(4):1076-1083
To achieve practical treatment of photo-processing waste (PW) using our previously proposed sulfur-oxidizing bacteria (SOB)/granular activated carbon (GAC) sludge system, this paper elucidates why 3- to 5-X dilution of PW was required. That is, a series of experiments were carried out to show the effects of high salinity and constituent organic compounds in PW, respectively. Both an inorganic salts system and calcination PW system showed that SOB completely oxidizes S2O(3)2- -S to SO(4)2- -S even at 12.3 or 13.6% salinity, respectively; hence the dilution requirement is not attributable to high salinity. In experiments employing SOB and SOB/GAC systems to investigate the effects of 23 constituent compounds in PW, compounds were classified into Groups I, II, IIIa, and IIIb. Even with 10 g/l GAC, the nine compounds in Group IIIb still exhibited a toxic effect on SOB activity at 1- and 3-X dilutions; thus it is these compounds that are responsible for requiring dilution of PW. Accordingly, a reduction in their use within the photodeveloping and fix-stabilizing industry, and/or use of > 10g/l GAC, are new considerations for establishing a more practical PW treatment process.  相似文献   
589.
The high risk of fire dieath and injury among elderly people is well documented. To be effective, fire safety education must reach older adults in the settings in which they reside: nursing homes and other long-term care institutions, board and care homes, and independent living facilities including the person's own home. Training must also be targeted at the people who are responsible for fire safety. In the case of the nursing home or board and care home, the responsible people are the staff and owners. In the case of the majority of older adults who live independently in their homes, it is either the individual or family members. These programs must also be comprehensive.A fire safety education curriculum was developed by a group of experts in a variety of related fields including fire safety, gerontology, health care industry, developmental disabilities, research, and instructional design. Older adults were included in each planning session. Based on that curriculum, workshops and workshop materials were developed for each of the three target populations: staff of health care facilities, staff and owners of board and care homes, and elderly people living independently in their homes. Materials included both print and audiovisuals. A pilot test of each workshop was conducted to test the short-term effects of the programs.Results indicated significant gains in knowledge for all groups and a significant improvement in positive attitudes toward fire safety for most participants. Measures of effects of the programs on intentions to change fire safety practices indicated a potential for change. Results also showed that the measured traits, knowledge of fire safety and attitudes toward fire safety, were relatively stable.  相似文献   
590.
Utilizing Bragg scattering near 90 degrees , an x-ray polarimeter is described that has high spectral resolution and reasonable efficiency. The latter is achieved by using a position-sensitive proportional counter to discriminate spatially resolved x rays dispersed by the crystal. This instrument has been used to measure the linear polarization of lines from one- and two-electron oxygen ions. For this study, aligned initial states have been populated in oxygen beams by various excitation processes in foil, gas, and thick solid targets. In spite of the small probability for the production and radiative decay of few-electron excited states in the presence of intense background radiation, the instrument resolution and efficiency are sufficient to permit polarization measurements.  相似文献   
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