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1.
Well-sintered CaO granules with hydration resistance are very important for the manufacturing and application of CaO-containing refractories. CaO granules with sol-processed metal oxide protective layers were prepared by granulation and surface treatment. The obtained results indicated that the usage of nano sol greatly improved the hydration resistance of CaO granules, especially when the CaO granules were treated by alumina sol. The promoting effect of nano sols in the sintering processes improved the density of CaO granules. Nanoparticles reacted with lime at lower temperature and a new phase was formed uniformly in the treated layer, which promoted densification of the treated layer. The grain size of CaO granules in the treated layer was increased obviously with the promotion of sintering. Moreover, nanoparticles were favorable for the formation of direct bonding between CaO grains by decreasing the dihedral angle.  相似文献   
2.
夏敏浩  赵万剑  王骏 《中州煤炭》2022,(7):189-194,200
为了提高配电网差异化节能降耗效果,解决现有潜力评估方法存在的应用性能差的问题,提出碳中和背景下配电网差异化节能降耗潜力优化评估方法。根据配电网的空间结构,构建相应的等值电路模型。在该模型下,从设备损耗和运行附加损耗2个方面计算配电网的损耗量。根据损耗量计算结果,确定配电网差异化碳中和节能降耗方式。从静态和动态2个角度设置潜力评估指标,通过指标数据处理、指标权重求解等步骤,得出配电网差异化节能降耗潜力的综合量化评估结果。将设计潜力评估方法应用到配电网的差异化节能降耗改造工作中,能够有效降低配电网的实际线损量、降低区域损耗费用,并具有较高的应用价值。  相似文献   
3.
有色冶炼过程中会产生大量的含砷酸性废水,除砷处理给企业生产运行带来了较大的压力,随着近年来冶炼废水中的砷含量逐步升高,高含砷污酸除砷处理受到了广泛的关注,如何实现经济、高效除砷成为当前的研究热点。对近年来高砷污酸处置技术:硫化法和石灰中和-铁盐法进行了总结与分析。并对尾渣固化除砷技术进行了归纳与展望。短期内硫化法除砷技术仍然为最受欢迎的主流技术,尾渣固化法在砷固定方面有较大优势,但应用过程中收到实际生产过程的制约,因此,该方法有较大的研究前景。  相似文献   
4.
Novel MgO-doped CaO sorbent pellets were prepared by gel-casting and wet impregnation. The effect of Na+ and MgO on the structure and CO2 adsorption performance of CaO sorbent pellets was elucidated. MgO-doped CaO sorbent pellets with the diameter range of 0.5-1.5 mm exhibited an excellent capacity for CO2 adsorption and adsorption rate due to the homogeneous dispersion of MgO in the sorbent pellets and its effects on the physical structure of sorbents. The results show that MgO can effectively inhibit the sintering of CaO and retain the adsorption capacity of sorbents during multiple adsorption-desorption cycles. The presence of mesopores and macropores resulted in appreciable change of volume from CaO (16.7 cm3∙mol1) to CaCO3 (36.9 cm3∙mol1) over repeated operation cycles. Ca2Mg1 sorbent pellets exhibited favorable CO2 capture capacity (9.49 mmol∙g1), average adsorption rate (0.32 mmol∙g1∙min1) and conversion rate of CaO (74.83%) after 30 cycles.  相似文献   
5.
过渡金属-氮共掺杂炭材料是一类高效的CO2电还原催化剂。以热解聚合物制备的氮掺杂炭材料为载体,浸渍镍源,经红外灯光照2 h,利用光化学法制备了高分散的镍-氮-碳催化剂(Ni/NC)。采用扫描电镜(SEM)、物理吸附、粉末X射线衍射(XRD)、X射线光电子能谱(XPS)等手段对催化剂的形貌、结构、物相和组成进行了分析,并评价了催化剂的CO2电还原反应性能。电化学性能测试结果表明,在0.5 mol/L的KHCO3电解液中,镍的负载量为2 %(质量分数)时催化性能最好,CO分电流密度得到有效提升,塔菲尔斜率为492 mV/dec,起始过电位为286 mV;在-0.6 V(vs.RHE)下,CO的法拉第效率为78%,在-1.0 ~-0.5 V(vs.RHE)内,n(CO)/n(H2)=0.5~3.6。  相似文献   
6.
针对传统退煮漂机产能低的问题,开发新型2+2型上下多层棉布(高支高密)高速高效退煮漂联合机。该联合机具有3大优点:(1)可调恒张力进布;(2)松紧架调速+张力(内应力)释放;(3)前后格轧车上下轧辊交换主动辊调节微布差。采用先进的透芯浸轧工作液和递洁清洗机理。设备配置了高效蒸洗单元机、动态循环过滤装置、前后一次加水装置和旋转式废热水热回收装置。该联合机工艺车速可达100~130 m/min,实际生产表明产能高,具有高效节能减排的特点。  相似文献   
7.
Sulfuric acid-catalyzed hydrolysis of cellulose commonly isolates cellulose nanocrystals (CNCs). Neutralizing the reactant solution with sodium hydroxide facilitates efficient downstream processing, but residual salt remains in the product. This study examines the reinforcing effects of CNCs from suspensions that contain residual salt on the mechanical properties of thermoplastic starch nanocomposites. By reinforcing starch films with up to 5 wt% CNCs, stiffness and strength are improved by 118% and 79%, respectively, indicating a good dispersion of CNCs in the starch matrix. Compared to nanocomposites incorporating salt-free CNCs, the remaining salt has no significant impact on the material's mechanical performance. The results indicate great potential of CNCs containing residual salt as biobased, low-cost nanofiller in hydrophilic polymer matrices.  相似文献   
8.
Bilinear systems are considered as a particular class of nonlinear systems including the state variables which are typically used for online identification. By using a recursive identification method and the maximum likelihood principle, this paper presents two recursive-based algorithms to identify the parameters of bilinear in parameter systems with ARMA noise. In this regard, recursive generalized extended least squares (RGELS) and recursive Maximum Likelihood (RML) algorithms have been proposed for identification of bilinear systems. These algorithms can be used as an alternative choice in system identification with acceptable performance. The proposed algorithms estimate the correlated noise parameters with high accuracy by making full use of the measurement data. Simulation results indicate that the proposed algorithms are effective for online identification of bilinear in parameter systems with high convergence speed.  相似文献   
9.
The ordered mesoporous NiRu-doped CaO-Al2O3 nanocomposites were synthesized via a facile evaporation-induced self-assembly method for CO2 methanation. Metallic Ni and Ru species retained the single-component heterostructure rather than NiRu alloy over the 600 °C-reduced catalysts. Owing to the synergistic effect of bimetallic Ni–Ru as well as the improved H2 and CO2 chemisorption capacities after the addition of Ru and CaO promoters, the ordered mesoporous 10N1R2C-OMA catalyst exhibited enhanced catalytic activity and selectivity, which achieved the maximum CO2 conversion of 83.8% and CH4 selectivity of 100% at 380 °C, 0.1 MPa, 30000 mL g?1 h?1. In a 550 °C-109 h-lifetime test, the ordered mesoporous 10N1R2C-OMA catalyst showed high stability and superior anti-sintering property due to the confinement effect of the ordered mesostructure.  相似文献   
10.
In the wake of increasing environmental constraints, this work is aimed at developing a catalyst purely prepared from waste biomass source as the raw material. The catalyst is investigated for its applicability in transesterification of vegetable oil with the objectives: (i) to use waste shells of mollusk as raw material for the preparation of activated carbon and CaO; (ii) to use it as heterogeneous catalyst in the transesterification of waste cooking oil; (iii) to optimize the different parameters affecting the transesterification reaction; and (iv) to study its reusability. Under optimized conditions it was observed that a conversion >90% was possible and the catalyst could be reused five times with a slight loss in activity. This study indicates that the biomass source could also be used as a potential raw material in the synthesis of environmentally benign catalysts.  相似文献   
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