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71.
Co-M/Al2O3上环己烷的选择性氧化研究 总被引:2,自引:1,他引:2
采用溶胶-凝胶法制备了Co-M/Al2O3(M=Cu,Zn,Ni)催化剂。在没有任何有机溶剂或助剂的条件下,研究了以空气为氧化剂的环己烷选择性氧化。所制备四种催化剂的活性为Co-Ni/Al2O3 >Co/Al2O3 >Co-Zn/Al2O3 >Co-Cu/Al2O3。在Co-Ni/Al2O3中Co、Ni的质量分数分别为4.0%和3.0%时活性最好。以Co-Ni/Al2O3为催化剂,在4.5 MPa、443 K下反应120 min,环己烷转化率达9.9%,环己酮和环己醇的总选择性达94.6%,n(酮)∶n(醇)为2.8。Co-Ni/Al2O3催化剂连续使用五次后活性基本不变。 相似文献
72.
To evaluate measurement uncertainty for small sample size and measurement data from an unknown distribution, we propose a grey evaluation method of measurement uncertainty based on the grey relation coefficient. The uncertainty of measurement is analyzed using grey system theory, and the defects of the grey evaluation model of measurement uncertainty (GEMU) are studied. We then establish an improved grey evaluation model of measurement uncertainty (IGEMU). Simulations show that the precision of IGEMU is greater than that of GEMU, and that sample size has only a small effect on the precision of IGEVU. In particular, IGEMU is applied to evaluating measurement uncertainty for small sample size and measurement data from an unknown distribution. The measurement uncertainty of total profile deviation, which is measured by the CNC gear measuring center, can be evaluated by a combination of IGEMU and the Monte Carlo method. 相似文献
73.
在多井筒分支水平井产量计算公式的基础上,结合国内某低渗油藏的物性建立地质模型。通过数值模拟计算分析,得到多分支水平井最优分支数量、最佳初始井筒压力、最佳井筒长度、井筒最佳位置,以及渗透率的垂向非均质性对水平井的产能影响。 相似文献
74.
结合青岛市游泳跳水馆看台的工程实践,提出了全新的看台施工方案,即看台梁板分两次浇筑,以及具体操作工艺,并重点阐述了看台板模板支设、钢筋绑扎、混凝土浇筑等关键技术,提出了保证施工方案顺利实施的诸多技术措施. 相似文献
75.
随着高校信息化的快速发展,高校网络管理中出现了工作业务范围广、工作量大、办公效率低等问题。根据校园网络管理的综合业务需求,需要将零散的业务进行分类整合,因此引人模块化管理思想和MVC模式,设计并完成了一套多权限模块化管理的校园网络管理协作办公系统。该系统具有多用户、多应用、多权限的管理功能。易扩展,并有较高的通用性和可移植性。 相似文献
76.
凝析气藏相态参数实验研究 总被引:1,自引:0,他引:1
油气藏流体主要有烃类成分组成,在油藏及地面条件下,这种烃类混合物的物理性质取决于其化学成分及给定的温度和压力。对于烃类的相态特征及流体组分研究在油气田开发中具有重要的意义,尤其是凝析气藏田。对海榆和10井的研究,归纳总结其流体PVT性质,为其开发提供科学依据。 相似文献
77.
In order to improve the location performance of User Equipment (UE) , enhance the availability of satellites navigation systems, an assisted Global Navigation Satellite System (GNSS) positioning algorithm based on Time Difference of Arrival (TDOA) technology is proposed for only three visible satellites in this paper. Using the structure of assisted satellite position system, UE was guaranteed to acquire navigation information of the three visible satellites rapidly, and three satellite observation equation were acquired, then the arrival time difference between UE and two adjacent base stations was used as an auxiliary, and a full-rank equation was constructed to achieve positioning by least squares method. The results showed that the algorithm had good convergence ability and positioning accuracy, and the confidence of this method’s positioning error, according to 3GPP request of assisted satellite navigation accuracy error within 50 m, reaches 94.56%, the average positioning accuracy was 16.8 m. The validity of this algorithm was demonstrated. 相似文献
78.
针对喇嘛甸油田特高含水期水驱精细调整需求,采用了高分辨率层序地层学原理与层次界面分析原理的储层沉积界面划分方法,研究河流—三角洲沉积背景下的单期河道单元沉积界面识别、划分与对比方法.提出井点砂体沉积微相以测井相图版为识别标准,依据沉积模式基本规律及演化规律研究各类砂体的平面分布特征.大大提高了井间各类砂体的识别精度,形成了高分辨率层序地层学原理指导下的河流—三角洲相储层沉积微相识别技术,有效指导特高含水期水驱精细调整,确保该区块在特高含水期含水不升、产量不降的高效开发效果. 相似文献
79.
80.
The direct calculation models of spectral transmittance of single and double slabs consisted of semitransparent solid materials were developed based on ray trace method, and a new inversion method of optical constants (k is extinction coefficient and n is refractive index) of materials was proposed based on transmittance spectrograms of double slabs. Differences between the new method and two others currently used methods were studied, and application range of methods was also investigated. Optical constants of selenide glass attained in references were selected as true values, and spectral transmittances of glass simulated based on direct calculation model were regarded as experimental values. Optical constants of selenide glass were achieved by inverse models. Influences of measurement error on inverse results were also determined. The results showed that: (1) based on transmittance spectrograms of double slabs in which thickness of single slab is the same, the new proposed method can attain optical constants of materials; (2) the effect of optical constants n and k on three inversion methods are urgent larger, but inversed calculation precision of optical constants are higher in most application ranges; (3) the influence of measurement errors existed in experimental datum on the inverse precision of three methods are urgent distinctness. 相似文献