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21.
基于表面反射率的赤潮卫星荧光线高度算法比较   总被引:8,自引:0,他引:8  
采用现场实测和室内培养两种方式测定了甲藻、赤潮异弯藻和叉角藻等赤潮藻以及新月菱形藻、海洋蓝绿藻、叉鞭金藻、塔胞藻、扁藻和小球藻等非赤潮藻类光谱曲线。采用的各卫星(MERIS,GLI,MODIS)的荧光波段数据按照其中心波长,从实际测定的高光谱反射率曲线提取而来,并按照荧光高度的计算公式得到其荧光高度。同时,采用统计分析方法建立荧光高度与叶绿素浓度的关系。10种藻类水体的荧光线高度与叶绿素α的回归分析结果显示了良好的线性关系,但部分藻种出现了负相关的结果。因为在高叶绿素浓度即赤潮条件下,浮游植物在荧光波段(685nm附近)和近红外波段(700~750nm)复杂的光谱行为,使得采用星载遥感器的叶绿素荧光波段探测某些藻类的赤潮时会出现偏差。同时,由于不同藻类的荧光高度与叶绿素浓度的关系也不一致,本文建议针对单独的赤潮种类应建立特定的荧光算法。相关问题还需要在实测的基础上进行更深入的研究。  相似文献   
22.
Waste stabilization ponds are widely used in many European countries, such as France and Germany, for the treatment of wastewater from mainly small communities. There would seem to be no reason why they should not also be a suitable treatment process for populations of under 2000 in the UK. The relative advantages and disadvantages of ponds are compared to other small community treatment systems, such as rotary biological contactors, biological filters and reed-bed systems, particularly in relation to effluent standards with respect to algae, nutrient removal and relative costs.  相似文献   
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24.
An accelerated water-streaming test method was used to evaluate several types of façade coatings regarding their behaviour to colonisation by algae and cyanobacteria, by closely reproducing the phenomenon of natural biological soiling. A set of materials with defined physical characteristics was thus investigated vs. the colonisation by algal and cyanobacterial strains isolated from natural façade biofilms. Porosity and roughness of the materials showed to be factors of influence in the establishment of those micro-organisms.  相似文献   
25.
本文旨在人工培养藻席,观察垫层的形成过程、氧化层、隔离层和还原层的转变,和其对聚矿及成矿的影响。  相似文献   
26.
The transportation of goods by sea results in vast amounts of water which is taken on as ballast, being transferred between ports, countries and continents. This can cause pollution, both chemical and biological. Public-health risks have also been identified. Although many countries, including the UK, have introduced guidelines on the discharge of ballast water, there are practical problems in establishing procedures which are suitable to mandatory control. Despite this, it is currently possible for ballast water discharges to fall within the ambit of the Scottish river purification authorities. This produces a dilemma in that an authority may have statutory duties which it does not have the practical or legal powers to fulfil. This paper explores the risks associated with uncontrolled ballast water discharge, the effectiveness of current controls, and possible further controls which could be exercised.  相似文献   
27.
The Mineral River contributes a significant amount of chloride to Lake Superior, more than one-third of the total U. S. tributary input. This unique discharge is attributed largely to the mine dewatering process of the White Pine Copper Company. Chloride concentrations as high as 2,000 mg/L have been recorded at the mouth of the Mineral River. The impact of this discharge on Lake Superior is not known; however, it is postulated that increased chloride concentrations may enhance the introduction and adaptation of marine organisms into the Great Lakes.  相似文献   
28.
甜菜果胶制备藻油乳化液及其稳定性研究   总被引:1,自引:0,他引:1  
藻油富含对人体非常重要的多不饱和脂肪酸DHA(二十二碳六烯酸),但其极易被光、热和氧等因素诱使发生氧化反应。防止氧化反应发生,制备成稳定的油/水乳化液将其包埋成为其在食品中应用的关键问题。本研究采用甜菜果胶为乳化剂对其进行乳化包埋,研究了乳化条件如乳化剂量、油水比率、pH和均质条件对乳化液稳定性的影响。结果表明,最适的乳化条件为:乳化剂添加量在2.5%以上,油水比1:10,pH〉5,35MPa压力下均质3个循环得到比较稳定的乳化液。  相似文献   
29.
The motivation for this research was to determine the influence of public policies on economic feasibility of producing algal biodiesel in a system that produced all its energy needs internally. To achieve this, a steady-state mass balance/unit operation system was modeled first. Open raceway technology was assumed for the production of algal feedstock, and the residual biomass after oil extraction was assumed fermented to produce ethanol for the transesterification process. The project assumed the production of 50 million gallons of biodiesel per year and using about 14% of the diesel output to supplement internal energy requirements. It sold the remainder biodiesel and ethanol as pure biofuels to maximize the rents from the renewable fuel standards quota system. Assuming a peak daily yield of 500 kg algal biomass (dry basis)/ha, the results show that production of algal biodiesel under the foregoing constraints is only economically feasible with direct and indirect public policy intervention. For example, the renewable fuel standards' tracking RIN (Renewable fuel Identification Number) system provides a treasury-neutral value for biofuel producers as does the reinstatement of the renewable fuel tax credit. Additionally, the capital costs of an integrated system are such that some form of capital cost grant from the government would support the economic feasibility of the algal biodiesel production.  相似文献   
30.
Foam flotation is an effective and energy efficient method of harvesting microalgae. This study has investigated the influence of growth phase and lipid content on harvesting efficiency. The highest biomass concentration factors were gained during active culture growth. Surprisingly, the quantities of lipid recovered from microalgae harvested by foam flotation using the surfactant cetyl trimethylammonium bromide (CTAB), were significantly higher than from cells harvested by centrifugation. Further, cells harvested by CTAB-aided foam flotation exhibited a lipid profile more suited to biodiesel conversion containing increased levels of saturated and monounsaturated fatty acids. The enhanced lipid recovery was partially explained by the interaction of the cells with the surfactant, CTAB, which adsorbed onto the algae and was carried over into the total lipid extraction process. However, further evidence also suggested that CTAB promoted in situ cell lysis by solubilising the phospholipid bilayer, thus increasing the amount of extractable lipid. This work demonstrates substantial added value of foam flotation as a microalgae harvesting method beyond energy efficient biomass recovery.  相似文献   
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