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81.
Data describing the distribution of diarrhetic shellfish poisoning toxins in 13 consignments of Danish-produced blue mussels are reported. The content of diarrhetic shellfish poisoning toxins was measured by a liquid chromatography coupled with tandem mass spectrometry detection method, and mean levels in the 13 consignments varied from 58 to 243 μg kg-1. The distributions of diarrhetic shellfish poisoning toxins in the consignments were relatively homogenous as the relative standard deviation of the content varied from 7 to 19%. The results are discussed in relation to food safety, the uncertainty of sampling and analysis, and the newly introduced European Union maximum levels of marine biotoxins in seafood products. 相似文献
82.
为了鉴定世界食品产品中受到很高评价的海洋生物的抗氧化性,研究了贻贝的抗氧化性。通过测定酶解物的抗氧化性,从胰蛋白酶、木瓜蛋白酶和胃蛋白酶3种酶中,筛选出木瓜蛋白酶和胰蛋白酶作为酶解贻贝制备具有较高抗氧化性酶解物的理想水解酶,用正交试验L9(34)对2种酶的水解条件进行了优化。结果表明,木瓜蛋白酶在温度60℃、酶解时间15min、pH7.5、酶质量分数1.00%的水解条件下,酶解物的抗氧化性最好;胰蛋白酶在温度50℃、酶解时间60min、pH8.5、酶质量分数0.75%的水解条件下,酶解物的抗氧化效果最佳。 相似文献
83.
Quagga mussels (Dreissena bugensis) have been linked to oligotrophication of lakes, alteration of aquatic food webs, and fouling of infrastructure associated with water supply and power generation, causing potentially billions of dollars in direct and indirect damages. Understanding their abundance and distribution is key in slowing their advance, assessing their potential impacts, and evaluating effectiveness of control strategies. Volume backscatter strength (Sv) measurements at 201- and 430-kHz were compared with quagga mussel veliger and zooplankton abundances determined from samples collected using a Wisconsin closing net from the Copper Basin Reservoir on the Colorado River Aqueduct. The plankton within the lower portion of the water column (>18 m depth) was strongly dominated by d-shaped quagga mussel veligers, comprising up to 95-99% of the community, and allowed direct empirical measurement of their mean backscattering cross-section. The upper 0-18 m of the water column contained a smaller relative proportion of veligers based upon net sampling. The difference in mean volume backscatter strength at these two frequencies was found to decrease with decreasing zooplankton abundance (r2 = 0.94), allowing for correction of Sv due to the contribution of zooplankton and the determination of veliger abundance in the reservoir. Hydroacoustic measurements revealed veligers were often present at high abundances (up to 100-200 ind L−1) in a thin 1-2 m layer at the thermocline, with considerable patchiness in their distribution observed along a 700 m transect on the reservoir. Under suitable conditions, hydroacoustic measurements can rapidly provide detailed information on the abundance and distribution of quagga mussel veligers over large areas with high horizontal and vertical resolution. 相似文献
84.
M. Azdi A. Moukrim T. Burgeot H. Budzinski J. F. Chiffoleau A. Kaaya 《Polycyclic Aromatic Compounds》2013,33(4):265-282
Specimens of the mussel Perna perna were collected along Moroccan coasts to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) bioaccumulated in the tissues, and to measure benzo[a]pyrene hydroxylase (BPH) activity. Chemical analysis of PAHs show that the Mediterranean (Nador, Martil, Tanger) and central Atlantic coasts (from Rabat to Jorf Lihoudi) are those most contaminated (351 245 ng.g? 1 dry weight in Tanger). The mussel contaminants were of mixed origin for most of the locations with non negligible inputs of petrogenic origin in many of them. Baseline levels of PAHs were between 6 and 55 ng.g? 1 dry weight. BPH activity showed significant correlation (r s = 0.64, P < 0.05) with total PAH concentrations at the six most contaminated stations. The baseline level of BPH activity can be identified as in the range 0.1 to 13 pmol.min? 1.mg prot? 1 along the Mediterranean and Atlantic coasts. 相似文献
85.
Nuray Erkan 《Journal of the science of food and agriculture》2005,85(15):2625-2630
The following chemical changes were observed during the cold storage of mussels for 6 days at 4 °C. Total volatile basic nitrogen (TVB‐N, mg N per 100 g) and trimethylamine values (TMA‐N, mg N per 100 g) were increased from 22.55 and 5.96 mg per 100 g at day 0 to 12.38 and 0.42 mg per 100 g, respectively, at the end of the storage period. The indole value and putrescine concentration were increased from 15.36 µg kg?1 and 24.7mg kg?1 to 34.46 µg kg?1 and 63.86 mg kg?1, respectively, on the fourth day of storage. The pH was slightly reduced and tyramine and cadaverine were not detected during storage. TVB‐N, TMA‐N and indole value could be selected as decomposition indicators for mussels during their cold storage. Acceptable limits of 15 mg per 100 g for TVB‐N, 3 mg per 100 g for TMA‐N, 35 µg kg?1 for indole and 60 mg kg?1 for putrescine are suggested. Sensory and chemical results indicated that the shelf‐life of mussels at 4 °C is limited to 4 days. Copyright © 2005 Society of Chemical Industry 相似文献
86.
Hong Lin Jie Jiang Chang‐hu Xue Bin Zhang Jia‐chao Xu 《Journal of the science of food and agriculture》2003,83(2):133-135
The phospholipids of mussels (Mytilus edulis Linne) from the coast of Qingdao were extracted, fractionated and analysed over a 12 month period. The contents of total lipids, neutral lipids, polar lipids and phospholipids were measured. The composition of phospholipids was determined by high‐performance liquid chromatography, and their fatty acid composition was analysed by gas chromatography. The phospholipid content ranged from 3.6 to 6.4 g kg?1 soft tissue. PE (phosphatidyl ethanolamine) and PC (phosphatidyl choline) were the major constituents. C16:0, C20:5 and C22:6 were the major fatty acids. C20:5 (5.25–23.10%) and C22:6 (6.05–20.42%) varied regularly with the seasonal factors. Their total amounts were high from January to June, which would be an optimal time for the utilisation of the phospholipids of mussels. © 2002 Society of Chemical Industry 相似文献
87.
《Journal of Great Lakes research》2020,46(3):528-537
Lake Michigan benthic macrofauna have been studied for almost a century, allowing for a unique analysis of long-term changes in community structure. We examined changes in abundances of three major taxonomic groups of benthic macroinvertebrates (Diporeia, Oligochaeta, and Sphaeriidae) in southern Lake Michigan from 1931 to 2015 and identified the most likely causes for these changes. Abundances of all three groups increased during 1931–1980 with the bulk of these increases occurring in nearshore (≤50 m) waters and coincident with increased loading of phosphorus (P) and subsequent increased primary production. Abundances of all three taxa declined during 1980–2000 again mostly in nearshore waters and coincident with decreased P loading. The quagga mussel (Dreissena rostriformis bugensis) invasion was associated with a further decline in phytoplankton primary production during 2000–2015. Both Diporeia and Sphaeriidae declined in abundance during that time, with Diporeia exhibiting the more pronounced decrease of the two groups. In contrast, Oligochaeta increased in abundance during 2000–2015. The quagga mussel has become, by far, the most abundant benthic macroinvertebrate species in terms of density and biomass. Overall, the primary driver of changes in the abundances of the three major taxa during this 85-year period appeared to be changes in phytoplankton primary production due to changing P loadings and, later in the time series, Dreissena filtering. The dreissenid mussels invasions coincided with a rapid decline of Diporeia abundance, but the mechanism of this negative effect remains unidentified. In contrast, Oligochaeta likely benefited from the quagga mussel invasion, perhaps via quagga-generated food supply. 相似文献
88.
Payap Masniyom Ommee Benjama Jaruwan Maneesri 《International Journal of Food Science & Technology》2012,47(5):1079-1085
Effect of turmeric and lemongrass essential oils (Eos) and their mixture on quality of green mussel stored at 4 °C was investigated. The mixture of 0.25% turmeric and 0.25% lemongrass Eos could lower microbiological and chemical deterioration of mussel as evidenced by the lower microbial counts, total volatile base, ammonia, trichloroacetic acid‐soluble peptide contents and thiobarbituric acid‐reactive substances, compared with the control (P < 0.05). It indicated that a mixture of turmeric and lemongrass Eos in mussel showed synergistic effect on the retardation of bacterial growth and lipid oxidation. However, samples treated with 0.5% lemongrass oil exhibited the higher likeness score for odour and flavour, compared with the samples treated with other Eos throughout the storage of 15 days. Samples treated with turmeric essential oil caused the changes in odour and flavour. Therefore, lemongrass treatment was shown to be the promising means to prevent the deterioration and maintain the odour and flavour attributes of mussel during prolonged refrigerated storage. 相似文献
89.
Utilization of waste freshwater mussel shell as an economic catalyst for biodiesel production 总被引:1,自引:0,他引:1
An economic and environmentally friendly catalyst derived from waste freshwater mussel shell (FMS) was prepared by a calcination-impregnation-activation method, and it was applied in transesterification of Chinese tallow oil. The as-prepared catalyst exhibits a “honeycomb” -like structure with a specific surface area of 23.2 m2 g−1. The newly formed CaO crystals are major active phase of the catalyst. The optimal calcination and activity temperature are 900 °C and 600 °C, respectively. When the reaction is carried out at 70 °C with a methanol/oil molar ratio of 12:1, a catalyst concentration of 5% and a reaction time of 1.5 h, the FMS-catalyst is active for 7 reaction cycles, with the biodiesel yield above 90%. The experimental results indicate that the FMS can be used as an economic catalyst for the biodiesel production. 相似文献
90.
以紫贻贝酶解液为原料,采用感官评价和GC-MS分析的方法研究Maillard反应制备海鲜风味基料的最佳工艺条件及产物的挥发性风味成分。结果表明:Maillard反应制备海鲜风味基料的最优模式体系为丙氨酸与脯氨酸的添加质量分数为0.5%、质量比为2:3、葡萄糖与木糖的总添加量为8%、质量比为1:3、反应pH6.2,反应温度为100℃、反应时间为25min;上述条件下制得的海鲜风味基料经GC-MS分析,鉴定出29种挥发性化合物,主要有羧酸类、吡嗪类、酯类、醛类、酮类、醇类、含硫类等化合物,对海鲜风味有贡献的化合物主要有苯并噻唑、3-甲硫基丙醛、吡嗪类等化合物。 相似文献