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41.
对影响页岩气单井产量的基质渗透率、人工裂缝(长度、条数)、天然裂缝(导流能力、连通性)及吸附气量等诸多参数进行模拟。结果发现,页岩气单井产量与上述参数均呈正比,而与天然裂缝间距成反比。通过大量的数值模拟计算进行了图版绘制,用BP人工神经网络法对各因素与改造体积的关系进行训练,以快速确定任意条件下的改造体积形状和大小。  相似文献   
42.
桥面铺面防水粘结层胶结材料洒布量的确定方法   总被引:2,自引:1,他引:1  
为确定桥面铺面防水粘结层胶结材料洒布量,采用橡胶沥青和两种典型的沥青混合料,通过设计直向剪切试验和斜向剪切试验研究桥面防水粘结层的力学性能,分析不同因素对于防水粘结层剪切性能的影响.试验结果表明,加载速率的提高,粘结层最大剪切应力有呈线性增大的趋势;采用不同温度的对比试验,同样发现随温度的升高,其抗剪切能力显著衰减.可以通过剪切试验的剪应力和变形能两个指标评价其剪切性能.  相似文献   
43.
Chlorpyrifos is a Malaysian Pesticide Board-approved organophosphate insecticide, which may become concentrated during fractionation. The objective of this project was to develop and validate a method to detect and quantify chlorpyrifos in food-grade fatty acids ingredients, e.g. caprylic-capric acid mixture and oleic acid (OLA) used to synthesize triacylglyceride based food additives and in the cosmetic industry. A selective ion monitoring gas chromatography–mass spectrometry method with a matrix-matched calibration curve calibration was selected. The method involved the direct injection of chlorpyrifos spiked into the fatty acids matrix. The percentage recoveries at spiking levels of 0.5, 0.75, 2.5, and 4.0 μg g−1 of chlorpyrifos in OLA and caprylic-capric acid ranged from 85.7%–101.1% to 97.2%–112%, respectively, with a relative standard deviation of within 11%. The intra-day and inter-day precision were deemed acceptable as indicated by an relative SD value of within 10%. A good linear relationship with a coefficient of correlation >0.99 for the matrix-matched calibration was achieved between 0.5 and 5 μg g−1. The limit of detection and limit of quantification corresponded to 0.5 μg g−1 for OLA and 0.55 μg g−1 for caprylic-capric acid.  相似文献   
44.
曲泓硕  张伦  张小松  纪文彬 《化工学报》2021,72(Z1):210-217
研究典型叉流式溶液除湿系统中,溶液循环流量(Gcir)、冷/热量(Qc/Qh)和系统流程对除湿/再生空气状态变化和除湿效果的影响机制。分析不同工况下空气在焓湿图中的过程曲线特征,比较各因素影响程度。结果表明,在设计条件下,当Gcir约为0.05 kg/s时,溶液除湿系统达到最佳除湿效果;当QcQh比例接近,总量由29.4 kW增加至48.9 kW时,系统中除湿量由3.7 g/kg上升至5.7 g/kg;不同流程中,当冷却对象为溶液时,溶液除湿效果较好。相较于溶液除湿系统中GcirQc/Qh,溶液除湿流程对空气状态变化和除湿效果的影响程度较大。空气过程曲线在各流程下具有显著特征,溶液除湿流程是影响空气状态变化和除湿效果的核心因素。  相似文献   
45.
稀土与二(2,4,4—三甲基戊基)膦酸固体配合物的研究   总被引:1,自引:0,他引:1  
合成了除Pm以外的16个稀土与二(2,4,4-三甲基戊基)膦酸(HBTMPP)的固体配合物,其组成为RE(BTMPP)_3,对配合物的性质进行了表征,热分析表明,在氩气中,热分解是一步完成的,在空气中,热分解分二步完成,前者的热分解产物是RE_4 (P_2O_7)_3,后者的产物为RE_2P_4O_(13)测定了配合物的振动光谱,对其主要吸收谱带进行了归属,配合物中RE-O键具有较高的离子特性  相似文献   
46.
热轧带钢卷取塔形产生原因及防范措施   总被引:2,自引:4,他引:2  
于千  杨健  余威  王伦  李瑞恒 《轧钢》2007,24(3):59-60
分析了热轧带钢卷取塔形产生的原因,对卷取过程中夹送辊、芯轴和助卷辊的速度控制,卷筒与轧机间的张力控制,侧导板控制,以及卷取区设备维护等方面进行改进后,卷取塔形问题有了很大改善。  相似文献   
47.
A microstrip‐fed conventional annular ring slot (ARS) antenna with linear polarization (LP) is initially studied. To generate two orthogonal degenerate modes for circular polarization (CP) radiations, two identical meandering perturbation slots (MPS) are symmetrically loaded into the ARS. By further incorporating a PIN diode switch across each MPS, the proposed antenna can switch between left‐hand CP (LHCP), right‐hand CP (RHCP), and LP. All three polarizations have shown good impedance bandwidth and broad CP bandwidth that can satisfy the wireless local area network (WLAN) 2.4‐GHz operating band (2400–2480 MHz). Furthermore, desirable gains of 1.8–2.0 dBi and 2.40–2.84 dBic are also exhibited at LP and LHCP/RHCP, respectively. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:110–120, 2016.  相似文献   
48.
机载雷达级联降维空时自适应杂波抑制方法   总被引:1,自引:1,他引:0  
提出一种机载雷达杂波抑制的级联降维空时自适应算法,即,先对全空时两维接收数据进行预滤波处理,将杂波局域化,降低杂波自由度;然后对预处理输出的信号的相关矩阵进行子阵划分,求解低维权向量,进一步降低运算量和采样要求。理论分析和实验仿真结果表明,所提算法具有良好的收敛性能和杂波抑制能力,并且对于阵元随机幅相误差和杂波起伏具有很好的容差能力。基于实测数据的实验验证了算法的有效性和稳健性。  相似文献   
49.
This study mainly focuses on the development of intelligent forecasting structures via a similar time method with historical load change rates for the hourly, daily and monthly load forecasting simultaneously based on the basic frameworks of fuzzy neural network (FNN) and particle swarm optimization (PSO). In the regulative aspect of network parameters, conventional back-propagation (BP) and PSO tuning algorithms are used, and varied learning rates are designed in the sense of discrete-time Lyapunov stability theory. The performance comparisons of different intelligent forecasting structures including neural network (NN) structure with BP tuning algorithm (NN-BP), FNN structure with BP tuning algorithm (FNN-BP), FNN structure with BP tuning algorithm and varied learning rates (FNN-BP-V), FNN structure with PSO tuning algorithm (FNN-PSO) and newly-designed adaptive PSO (APSO) structure are verified by numerical simulations. In order to verify the effectiveness of the superior APSO forecasting structure in practical energy-saving load regulation, the load forecasting during every 15 min is also given, and its result is used to manipulate the scheduled unloading control of a real case in Taiwan campus.  相似文献   
50.
Different doses of ketamine (10 mg/kg, 20 mg/kg, 30 mg/kg, 40 mg/kg, 50 mg/kg, and 60 mg/kg) were injected i.p. (I.P.), respectively, to male ICR mice to determine the optimal dosage for chronic administration. At and above 40 mg/kg I.P. injection, mice had almost no hindlimb movement during swimming test. Subsequently, 30 mg/kg was used as the dose for the study in the toxicity of long-term ketamine administration on urinary bladder and sperm motility. The treatment group were subdivided into two (n = 10 each group); one received daily ketamine treatment i.p. for 3 months and another group for 6 months. Corresponding number of mice in control groups (n = 5 each group) received saline injection instead of ketamine. Terminal dUTP nick and labeling (TUNEL) study and Sirius red staining were carried out on the sectioned slides of the urinary bladders to study the degree of apoptosis in both epithelium and muscular layers of the urinary bladder and the relative thickness of the muscular layers in this organ was also computed. Apoptosis in the bladder epithelium was observed initially in the 3-month ketamine treated mice and the number of apoptotic cells was significantly different (P < 0.05) between the 3-month and 6-month ketamine treated mice and the control. The relative thickness of muscular layers in the bladder wall also decreased significantly (P < 0.05) when the 6-month treated mice and the control were compared. Sirius red staining revealed increase of collagen in the urinary bladder of the treated mice, most evidently 6 months after ketamine treatment. In addition, the sperm motility was studied and there was a statistically significant difference between the control and ketamine treated groups in the percentages of sperms which were motile (P < 0.05). This suggested that the chronic administration of ketamine affected the genital system as well.  相似文献   
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