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41.
Research bearing on several popular conceptions of the major determinants of anger arousal indicates that the particular appraisals often identified as causes of anger frequently only serve to affect the intensity of the anger that is generated. Research into effects of physical pain or other physically unpleasant conditions or involving social stresses suggests that decidedly aversive conditions are a major spur to anger. Experiments are also reviewed showing that anger-related muscular movements can also lead to anger-related feelings, memories, cognitions, and autonomic responses. Alternative explanations for the findings are discussed. The authors urge emotion theorists to widen their methodology and analyses so that they give careful, detailed attention to the many different factors that can influence anger. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
This paper presents an exact non‐reflecting boundary condition for dealing with transient scalar wave propagation problems in a two‐dimensional infinite homogeneous layer. In order to model the complicated geometry and material properties in the near field, two vertical artificial boundaries are considered in the infinite layer so as to truncate the infinite domain into a finite domain. This treatment requires the appropriate boundary conditions, which are often referred to as the artificial boundary conditions, to be applied on the truncated boundaries. Since the infinite extension direction is different for these two truncated vertical boundaries, namely one extends toward x →∞ and another extends toward x→‐ ∞, the non‐reflecting boundary condition needs to be derived on these two boundaries. Applying the variable separation method to the wave equation results in a reduction in spatial variables by one. The reduced wave equation, which is a time‐dependent partial differential equation with only one spatial variable, can be further changed into a linear first‐order ordinary differential equation by using both the operator splitting method and the modal radiation function concept simultaneously. As a result, the non‐reflecting artificial boundary condition can be obtained by solving the ordinary differential equation whose stability is ensured. Some numerical examples have demonstrated that the non‐reflecting boundary condition is of high accuracy in dealing with scalar wave propagation problems in infinite and semi‐infinite media. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
43.
盐家油田油水井结垢原因探讨   总被引:2,自引:0,他引:2  
对地层温度65~75℃的盐家油田油水井近井地带、井底、井筒发生严重结垢的原因进行了分析探讨。7口油井采出的地层水均为NaCO3型水.矿化度6.4~10g/L,HCO3浓度高(1.6~3.7g/L),Ca^2++Mg^2+浓度较低;1口水源井水及1口水井注入水为CaCl2型水,矿化度32~33g/L,Ca^2++Mg^2+浓度高(3.1~3.8g/L)而HCO3浓度低;采用CaCO3饱和指数法和CaSO4热力学溶解度法预测,在70℃下所有水样均有CaCO3结垢趋势,除3口油井采出的地层水外,均有CaSO4结垢趋势。3口油井采出的地层水与水源水在25℃按不同比例混合后,悬浮物含量大幅度上升。在70℃放置7天后再次大幅度上升,烘干的悬浮物易溶于稀盐酸.其主要成分为碳酸盐.说明注入水、地层水不配伍。1口电泵采油井和1口注水井油管垢样含盐酸可溶物(碳酸盐)超过90%。讨论了碳酸盐、硫酸盐垢的生成条件:温度、压力及pH值。图1表4参3。  相似文献   
44.
三叶状钒催化剂的研制   总被引:1,自引:0,他引:1  
介绍了三叶状钒催化剂的研制。工业宏观活性评价和通气测试表明,三叶状催化剂性能优良,其床层压力降介于圆柱状和环状催化剂之间,为圆柱状催化剂的70%左右。在相同的转化条件下,相对于环状催化剂,三叶状催化剂的装填量可减少16.7%。  相似文献   
45.
The main problems in estimating the uncertainty due to the presence of impurities in the material: the absence in the documents of a unique definition of the quantity being measured – the fixed point temperature, the lack of agreed methods of realizing the fixed points and the insufficient justification of the equations used for the estimate, are analyzed. The results of a measurement of the melting point of gallium are presented, which differ in the conditions in which they were realized – with one and two liquid-solid interfaces and different solidification conditions, are presented. The reasons for the considerable difference between the values of the temperatures obtained in these experiments are discussed.  相似文献   
46.
47.
Hakan Boyaci 《Sadhana》2006,31(1):1-8
A simply supported damped Euler-Bernoulli beam with immovable end conditions are considered. The concept of non-ideal boundary conditions is applied to the beam problem. In accordance, the boundaries are assumed to allow small deflections and moments. Approximate analytical solution of the problem is found using the method of multiple scales, a perturbation technique.  相似文献   
48.
ABSTRACT: We evaluated the effect of growth environment on morphology and fatty acid (FA) profiles of 2 strains of C ampylobacter jejuni (ATCC 29428 and 33560) grown under various gaseous conditions. Viable counts were determined by plate count and percentages of coccoid cells. FA profiles were measured by gas chromatography. Plate counts were lowest when cultures were grown in air and highest in CO2 (10%), O2 (5%), and N2 (85%). For 29428, percentages of coccoid cells did not differ among treatments. For 33560, percentages of coccoid cells were greater than for 29428 and varied among treatments (13% to 87%). There were no significant ( P > 0.05) relationships between percentages of coccoid cells and amounts of individual or combinations of FA either between or within strains.  相似文献   
49.
The macroscopic deformation behavior of a fiber-reinforced aluminum-boron composite is investigated. Different periodic and random arrangements of the microstructure are considered with macroscopic hardening behavior due to the evolution of plastic zones on the microscale being taken into account.

For the solution of the initial boundary value problem, a non-standard algorithm is applied. It consists of the direct solution of the whole set of equations, treating all variables as global quantities. Together with a higher order time integration method (BDF2), an automatic step size control is used in the FEM calculations.  相似文献   

50.
Hypnosis has been demonstrated to reduce analogue pain, and studies on the mechanisms of laboratory pain reduction have provided useful applications to clinical populations. Studies showing central nervous system activity during hypnotic procedures offer preliminary information concerning possible physiological mechanisms of hypnotic analgesia. Randomized controlled studies with clinical populations indicate that hypnosis has a reliable and significant impact on acute procedural pain and chronic pain conditions, Methodological issues of this body of research are discussed, as are methods to better integrate hypnosis into comprehensive pain treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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