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81.
Herein, a facile one‐step surface modification technique of coating functional biopolymer conjugated mussel‐inspired catechol (CA) onto substrate is applied to confer polyethersulfone (PES) membranes with remarkable blood compatibility, antifouling property, and antibacterial property, respectively. CA conjugated poly(2‐acrylamido‐2‐methylpropanesulfonic acid) (PAMPS), poly(sulfobetaine methacrylate) (PSBMA), and poly(methacryloxyethyltrimethyl ammonium chloride) are synthesized via free radical polymerization in the presence of CA, and simultaneously coated onto PES membrane surface. The surface chemical compositions, surface zeta‐potential convince the successful preparation of the modified PES membranes. PAMPS‐coated membrane exhibits excellent blood compatibility, especially anticoagulation property; PSBMA‐coated membrane displays excellent antifouling property and blood compatibility; meanwhile, PDMC‐coated membrane shows robust bactericidal property. In general, this work demonstrates that the mussel‐inspired surface modification protocol provides a facile and versitile method to confer the substrate with excellent blood compatibility, antifouling property, and antibacterial property, respectively, which has great potential for multibiomedical applications, such as blood purification, hemodialysis, and organ implantation.  相似文献   
82.
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   
83.
传统的防污剂对海洋环境造成严重污染,随着环保意识的增强以及相关规定的制订,各国竞相开展新型无毒防污剂的研究。本文以海洋产蛋白酶菌株发酵产物为活性物质,研究蛋白酶粗提物对污损生物硅藻(navicula sp.)和贻贝(mytilus edulis)附着行为的影响。结果表明,所研究菌株的发酵液对硅藻(navicula sp.)和贻贝(mytilus edulis)的附着有明显抑制作用。贻贝(mytilus edulis)毒性实验显示,细菌发酵液对贻贝无毒。因此,海洋微生物蛋白酶产生菌粗酶提取物可以作为环保型防污功能添加剂。  相似文献   
84.

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.
响应面法优化微波辅助提取贻贝蛋白的工艺研究   总被引:1,自引:1,他引:0  
研究微波对中性蛋白酶水解贻贝蛋白条件的影响,探讨了在一定的微波功率/时间,加酶量、酶解温度和时间对蛋白质回收率的影响。单因素实验先确定因素水平,再通过响应面确定最佳的工艺条件,酶解条件分别是时间为118.8min,加酶量为0.754%,微波功率为189.7W,温度分别为46.9℃,该条件下得到的最大蛋白质回收率为74.83%。  相似文献   
86.
Calcined mussel shells have been used as new low cost and eco-friendly biosorbent for the removal of safranin as cationic dye from aqueous solutions by biosorption technique. Batch mode experiments were conducted using various parameters such as pH, contact time, biosorbent amount and safranin concentration. Removal efficiency of safranin by the calcined mussel shells attained 87.56% using 200 mg of biosorbent and 150 mg/L as safranin concentration and for a pH above 9.2. Four kinetic models are used, pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion for the design and the optimization treatment. The kinetic analysis showed that the pseudo-second-order model had the best fit to the experimental data. Biosorption isotherms were also investigated using Langmuir, Freundlich and Temkin models. The experimental data fitted very well with both Langmuir and Freundlich isotherm models. Thermodynamic biosorption processes were found to be spontaneous, endothermic. The Gibbs energy ΔG° decreased from −1.956 kJ/mol to −2.456 kJ/mol with increase in temperature from 298 K to 313 K indicating a increase in feasibility of biosorption at higher temperature. Accordingly, calcined mussel shells were shown to be a very efficient, eco-friendly and low cost biosorbent and a promising alternative for removal dyes from aqueous solutions.  相似文献   
87.
Anderson MA  Taylor WD 《Water research》2011,45(17):5419-5427
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   
88.
In order to identify nutraceutical functions of fermented fish and shellfish sauces, which are highly appreciated in food products in South-East Asia, the antioxidative activity of fermented blue mussel sauce (FBMS) was investigated. The blue mussel was fermented with 25% NaCl (w/w) at 20±0.5 °C for 12 months and the fermented sauce was passed bimonthly through a 40-mesh sieve, desalted using an electrodialyzer, and then lyophilized. The antioxidative activity of FBMSs was investigated and compared with that of a natural antioxidant, -tocopherol standing as a reference. Using consecutive chromatographic methods, the antioxidative peptide with a molecular mass of 620 Da was purified from 6-month-fermented sauce, and its sequence of the peptide was FGHPY. In addition, 64.8 M of the purified peptide could scavenge 89.5% of hydroxyl radical in radical scavenging assay using electron spin resonance spectroscopy.  相似文献   
89.
沼虾饲料中贻贝液与植物油脚的最适添加量   总被引:1,自引:0,他引:1  
通过对在罗氐沼虾饲料中,贻贝制品废弃液和植物油脚的不同添加量的投饲试验,以体长增长和个体质量增加以及成活率为指标,经统计分析,结果表明:饲料中最经济且有效的添加量为贻贝液与油脚各添加1%~2%,相应的胆固醇质量分数为2.2×10(-3)~3.78×10(-3)。  相似文献   
90.
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   
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