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71.
针对卫10块已进入中高含水开发期,区块综合含水上升快,自然递减居高不下等问题,在地层精细对比、构造精细解释、沉积微相、储层综合评价、剩余油分布规律研究的基础上;通过以中部封堵、拉大注采井距,边部加强平面及层间动用为主要治理方向的实施,提高了注入水利用率,提高区块分层动用程度,控制了区块含水上升速度,改善注水开发效果,探索出了一套适合中高含水期低渗透复杂断块油田剩余油挖潜治理的方法。  相似文献   
72.
废水pH对超滤膜过程的影响   总被引:2,自引:0,他引:2  
研究了pH变化对废水中胶体微粒粒径/粒径分布、Zeta电位及超滤过程中溶液通量衰减指数的影响.结果表明,当废水pH为7.14时,废水中胶体微粒和粒径分布达到最大、滤液中总铁含量小于0.1 mg·L~(-1);当pH大于9.6时,废水中荷负电胶体微粒的Zeta电位达到-32 mV.超滤过程中的溶液通量衰减指数表明,废水pH在弱碱性条件下的超滤膜污染较中性或酸性条件下小.  相似文献   
73.
This paper presents the results of a study of the effectiveness of submerged sacrificial anodes in preventing the onset of pitting corrosion in the emerged part of marine piles. Experimental tests were carried out on reinforced concrete columns with steel embedded both in chloride free concrete and chloride contaminated concrete in order to compare the effects of sacrificial anodes on passive steel and on corroding steel. Results have shown, at least under the present testing conditions, that sacrificial anodes may be more effective in preventing corrosion initiation (i.e. in providing cathodic prevention) than in controlling ongoing pitting corrosion (i.e. in guaranteeing cathodic protection). Monitoring criteria for this type of prevention are also discussed.  相似文献   
74.
本文用地质累积指数和潜在生态危害指数对鄱阳湖重金属污染进行评价,结果表明:(1)评价结果表明鄱阳湖区重金属污染主要为Cu污染。鄱阳湖重金属污染的主要来源是德兴铜矿,其中Cu当然是主要污染物,因此,评价结果与实际情况是吻合的。(2)Cu、Zn、Cd污染源相同且来源于德兴铜矿,Pb表现为面源污染。湖区Cu、Zn、Cd分布均表现出从饶河段至湖口逐步降低的趋势,且Cu、Zn、Cd在土壤中的含量呈现显著的相关性和偏相关性,可以推论Cu、Zn、Cd污染源相同且来源于德兴铜矿。Pb在湖区均匀分布表现为面源污染,这可能与湖区Pb污染来源于船舶燃油有关。  相似文献   
75.
Production and dispersion stability of nanoparticles in nanofluids   总被引:4,自引:0,他引:4  
This paper presents an experimental study on the homogeneous dispersion of nanoparticles in nanofluids. In this study, various physical treatment techniques based on two-step method, including stirrer, ultrasonic bath, ultrasonic disruptor, and high-pressure homogenizer were systematically tested to verify their versatility for preparing stable nanofluids. Initially carbon black and silver nanoparticles dispersed in base fluids with the presence of surfactant were found to be highly agglomerated with the hydrodynamic diameter of 330 nm to 585 nm, respectively. After both CB and Ag nanofluids were treated by various two-step methods, stirrer, ultrasonic bath, and ultrasonic disrupter was found to do a poor performance in deagglomeration process for the initial particle clusters. However, the high-pressure homogenizer produced the average diameter of the CB and Ag particles of 45 nm and 35 nm, respectively, indicating that among various physical treatment techniques employed in this study, the high-pressure homogenizer was the most effective method to break down the agglomerated nanoparticles suspended in base fluids. In order to prepare another nanofluid with much smaller primary nanoparticles, we also employed a modified magnetron sputtering system, in which the sputtered nanoparticles were designed to directly mix with the running surfactant-added silicon oil thin film formed on a rolling drum (i.e. one-step method). We observed that Ag nanoparticles produced by the modified magnetron sputtering system were homogeneously dispersed and long-term stable in the silicon oil-based fluid, and the average diameter of Ag nanoparticles was found to be ~ 3 nm, indicating that the modified magnetron sputtering system is also an effective one-step method to prepare stable nanofluids.  相似文献   
76.
The inhibition effect of 2-mercaptothiazoline (2MT) on the corrosion behavior of mild steel (MS) in 0.5 M HCl solution was studied in both short and long immersion times (120 h) using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) techniques. For long-term tests, hydrogen gas evolution (VH2t) and the change of the open circuit potential with immersion time (Eocp − t) were also measured in addition to the former three techniques. The surface morphology of the MS after its exposure to 0.5 M HCl solution with and without 1.0 × 10−2 M 2MT with the different immersion times was examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The thermal stability of the inhibitor film was investigated by thermogravimetric analysis (TGA). The value of activation energy (Ea) for the MS corrosion and the thermodynamic parameters such as adsorption equilibrium constant (Kads), free energy of adsorption (ΔGads), adsorption heat (ΔHads) and adsorption entropy (ΔSads) values were calculated and discussed. The potential of zero charge (PZC) of the MS in inhibited solution was studied by the EIS method, and a mechanism for the adsorption process was proposed. The results showed that 2MT performed excellent inhibiting effect for the corrosion of the MS. Finally, the high inhibition efficiency was discussed in terms of adsorption of inhibitor molecules and protective film formation on the metal surface. TGA results also indicated that the inhibitor film on the surface had a relatively good thermal stability.  相似文献   
77.
Stable YAG (Y3Al5O12) aqueous slurry with ammonium polyacrylate (NH4PAA) polyelectrolytes as dispersant was prepared by ball mill method. The effects of polyelectrolyte concentration and pH value on the stability of the suspension is described here, and the stability maps are constructed at different pH value and polymer concentration. The rheological behavior of YAG slips of different solid loading (60–70%) has been studied by measuring their viscosity and shear stress as a function of shear rate and pH of the slurry. An optimal amount of dispersant and pH value for the suspension was found. YAG suspension displays a maximum in zeta potential values and a minimum viscosity in pH range of 9–11. Slips behaved as near Newtonian at the pH value up to a solid loading of 60 wt% and as non-Newtonian with thixotropic behaviors above this solid loading value. The density and the green as well as sintered microstructure of the cast products bear a direct relationship to the state of this slips induced by the alternation in the pH and the concentration of the dispersant as well as solid loading.  相似文献   
78.
在分析了液压系统常见的能耗问题的基础上,以现有的某型号液压挖掘机动臂液压系统为研究对象,设计了新型动臂势能回收系统,并建立该系统的AMESim模型。通过仿真分析得出新液压系统的能源利用率比不采用任节能措施的液压系统提高了34.8%,有良好的节能效果。  相似文献   
79.
The field signature method (FSM) is a nondestructive testing (NDT) method based on the potential drop (PD) technique and has been applied to online metal pipe corrosion monitoring for nearly three decades. The many advantages and benefits of the method have been reported in a number of studies, but few have reported on its limitations or shortcomings. However, the detection accuracy for pitting corrosion in FSM is very low. In this paper, the reasons for the low pitting corrosion detection accuracy of FSM were analyzed and it was found that different corrosion pits, which have different sizes, depths or positions, generally have differing influences on the potentials of nearby electrode pairs. Therefore, a new method using a subdivided resistor network to assess pitting corrosion is proposed and verified. When compared with the traditional method, the most important parameter, namely the pitting corrosion depth detection accuracy, can be significantly improved.  相似文献   
80.
目前濮城油气田南区沙二上1-3气顶气藏已进入后期开发,气井普遍水淹,严重影响了气井的正常生产。为了解决这一问题,根据不同气井水淹的具体情况,分别对气藏的气井应用了小泵加气锚、泡排、液氮气举、下电泵、酸化等配套工艺技术对气藏进行挖潜,取得了较好的采气效果。  相似文献   
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