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101.
提出了用精馏塔对含氮天然气脱除N2生产液化天然气(LNG),精馏塔塔釜液位的一种控制方法。该方法以脱氮分离效率和稳定的产品(LNG)出料温度为控制目标,建立了塔釜液位控制模型并仿真。整个闭环控制模型包括被控对象传递函数,调节阀传递函数,PID控制传递函数和检测传递函数。其中调节阀传递函数的建立,采用先计算阀位-Cv值(流量系数)曲线;然后通过系统辨识法[1]求得数学模型;最后利用泰勒级数把非线性化转化为线性化并求得传递函数。通过Matlab软件[2]的仿真,在阶跃干扰下,得到了合适的液位变化曲线和合适的阀位变化[3]。 相似文献
102.
介绍瓮福磷肥厂重钙(TSP)装置改产DAP后,反应与尾气洗涤系统料浆泵、搅拌器、反应器、洗涤泵、重要阀门在运行中出现的问题及处理措施. 相似文献
103.
This paper presents the real-time application of the learning control theory to the control of a chemical pilot plant: a pulsed liquid-liquid extraction column.
The behaviour of an agitated liquid-liquid extraction column can be related to random mechanisms such as the phenomena of droplets breakage and coalescence. Previous studies on hydrodynamic and mass transfer aspects showed that a pulsed liquid-liquid extraction column had an optimal behaviour for operating conditions close to flooding. These results led to choose the following strategy to control the column in its optimal behaviour zone:
- the measure of the conductivity of the liquid medium below the distributor which gives a good information about flooding, is the controlled variable
-the pulse frequency is the control action.
The learning control algorithm is based on a multilevel system of automata which operates in a random environment. By means of an evaluation unit of the performances of the column which generates either penalty (inaction) or reward on the basis of heuristic rules, the automaton chooses a value of the pulse frequency. This approach is essentially connected to artificial intelligence in so far as human knowledge on the plant is included in these rules.
This algorithm has been implemented on a microcomputer for control purposes. The experimental results presented show the good performances of the approach. 相似文献
The behaviour of an agitated liquid-liquid extraction column can be related to random mechanisms such as the phenomena of droplets breakage and coalescence. Previous studies on hydrodynamic and mass transfer aspects showed that a pulsed liquid-liquid extraction column had an optimal behaviour for operating conditions close to flooding. These results led to choose the following strategy to control the column in its optimal behaviour zone:
- the measure of the conductivity of the liquid medium below the distributor which gives a good information about flooding, is the controlled variable
-the pulse frequency is the control action.
The learning control algorithm is based on a multilevel system of automata which operates in a random environment. By means of an evaluation unit of the performances of the column which generates either penalty (inaction) or reward on the basis of heuristic rules, the automaton chooses a value of the pulse frequency. This approach is essentially connected to artificial intelligence in so far as human knowledge on the plant is included in these rules.
This algorithm has been implemented on a microcomputer for control purposes. The experimental results presented show the good performances of the approach. 相似文献
104.
105.
针对初冷器喷洒洗萘存在的堵塞和阻力大等问题,相应采取了改进工艺和调整操作参数等措施,即确保了出厂煤气的质量,又提高了生产的安全性。 相似文献
106.
Lipase-catalyzed alcoholysis of soy phospholipids was investigated to simultaneously make lysophospholipids and fatty acid
esters of individual alcohols. Alcoholysis was carried out by stirring a mixture of soy phospholipids and individual alcohols
in equimolar proportions with 10% (by weight of reactants) Mucor miehei lipase at 55°C for 24 h. The products were isolated by column chromatography after removal of the lipase. Lysophospholipids
(in 69–78% molar yield) were obtained from soy phospholipids, and the yield of esters of various alcohols also conformed nearly
with theoretical yields. 相似文献
107.
分析了氯气的洗涤冷却效果等影响氯气干燥质量的因素,提出改进氯水洗涤塔洗涤效果、稳定干燥塔运行工况、降低氯气中酸雾夹带以及提高酸雾捕集效果的措施。 相似文献
108.
109.
气—液鼓泡塔中流动域和气含率的分布 总被引:1,自引:0,他引:1
利用压力传感器测定了气、液两相鼓泡塔内不同轴、径向位置上压强的脉动信号,分析了压强的脉动特征,计算了各种操作条件下塔内不同轴向位置截面上的平均气含率,发现在不同操作条件下,塔内可能出现不同的流动域分布,即全塔均匀鼓泡域、全塔过渡域、全塔湍动鼓泡域以及均匀鼓泡域,过渡域和湍动鼓泡域中的相邻2种或3种流域同时出现在塔内不同高度上。提出了不同轴向位置流域转变的判据。并发现,同一截面的不同径向位置基本处于同一流域内。同时研究了鼓泡塔内气含率在轴向上的分布规律,给出了不同流动域内气含率的关系式。 相似文献
110.
The characteristics of gas bubbles in a 5 cm diameter bubble column equipped with a single orifice of 1,3 or 5 mm diameter were investigated under system pressure of 0.1-15 MPa. The formation of gas bubbles was strongly affected by the system pressure. Under high pressures a dispersed gas jet was formed at gas velocities where spherical gas bubbles would have been formed at atmospheric pressure. The critical gas velocity between the bubbling regime and the jetting regime was correlated with the liquid phase Weber number and the gas phase Reynolds number based on the gas velocity at the orifice. Bubble size and gas holdup in the main part of the bubble column were also affected by the bubble formation pattern at the distributor 相似文献