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101.
研究了常温溶剂法合成抗氧剂3114反应热力学和动力学过程。控制温度在117±2℃,研究结果表明,反应是零级反应,反应速率常数k=1.91×10-3/min,反应的平衡常数K=138.4(mol/L)-6,反应活化能Ea=1366.2J/mol。  相似文献   
102.
超临界条件下苯酚在NKA-Ⅱ树脂上的吸附相平衡   总被引:3,自引:0,他引:3       下载免费PDF全文
测定了苯酚在常规条件 (以水作为流体 )下在极性、弱极性和非极性吸附树脂上的吸附等温线 ,研究了“苯酚 +NKA -Ⅱ树脂 +超临界CO2 ”体系的吸附相平衡关系 ,测定了苯酚在NKA -Ⅱ树脂上的超临界吸附等温线 ,考察了超临界条件下乙醇作为添加第三组分的对苯酚在NKA -Ⅱ树脂上的吸附等温线的影响 .结果表明 :苯酚在极性吸附树脂上的平衡吸附量要远大于在弱极性和非极性吸附树脂上的平衡吸附量 ,在超临界条件下 ,苯酚在树脂上的吸附量远小于在常规条件 (如水作为流体 )苯酚在树脂上的吸附量 ,而且乙醇的添加又将能改变超临界吸附相平衡 ,使苯酚在NKA -Ⅱ树脂上的平衡吸附量进一步减少 .可以利用这些特性开发超临界流体再生吸附剂技术  相似文献   
103.
Detailed in situ absorption spectral investigation of chemical oxidative polymerization of aniline in dodecylbenzene sufonic acid (DBSA) based system revealed that the chain propagation is assisted by redox equilibrium intermediate (REI) rather than a fully oxidized pernigraniline. The continuous reduction (addition of aniline) and oxidation (by oxidant) of REI, propagate the chain. The polymerization process consists of three prominent stages called induction period (IP), chain propagation and termination. The initial stage of polymerization is realized as IP, the time taken to establish REI. The presence of fully developed polaron band indicates REI has delocalized structure. Invariant spectral features together with tremendous increase in absorbance at propagation phase indicate REI undergoes reductive addition of aniline and oxidation by APS (ammonium persulfate) while maintaining equilibrium structure. The greatly increased absorbance with time at this stage is due to well-known autoacceleration phenomenon observed for aniline polymerization. The increase in redox potential of REI with increase in chain length accelerates the reaction and accounts for autoacceleration. The termination of polymerization would be reduction or oxidation depending on the availability of aniline or oxidant respectively. In a system where the oxidant is the limiting agent, reduction continues until it reaches emeraldine salt that is incapable of further reduction. On the other hand an excess of oxidant, results in the formation of pernigraniline by continuous oxidation.  相似文献   
104.
本文由无限稀释活度系数求取混合物MH-81状态方程的二元相互作用参数,预测了二元混合物的汽液平衡,获得了较满意的结果。  相似文献   
105.
To study the feasibility of CO2 geological sequestration,it is needed to understand the complicated mul- tiple-phase equilibrium and the densities of aqueous solution with CO2 and multi-ions under wide geological condi- tions(273.15—473.15K,0—60MPa),which are also essential for designing separation equipments in chemical or oil-related industries.For this purpose,studies on the relevant phase equilibria and densities are reviewed and analyzed and the method to improve or modify the existing model is suggested in order to obtain more reliable predictions in a wide temperature and pressure range.Besides,three different models(the electrolyte non random two-liquid(ELECNRTL),the electrolyte NRTL combining with Helgeson model(ENRTL-HG),Pitzer activity coefficient model combining with Helgeson model(PITZ-HG))are used to calculate the vapor-liquid phase equilib- rium of CO2-H2O and CO2-H2O-NaCl systems.For CO2-H2O system,the calculation results agree with the experimental data very well at low and medium pressure(0—20MPa),but there are great discrepancies above 20MPa.For the water content at 473.15K,the calculated results agree with the experimental data quite well.For the CO2-H2O-NaCl system,the PITZ-HG model show better results than ELECNRTL and ENRTL-HG models at the NaCl concentration of 0.52mol·L ^-1 .Bur for the NaCl concentration of 3.997mol·L ^-1 ,using the ELECNRTL and ENRTL-HG models gives better results than using the PITZ-HG model.It is shown that available experimental data and the thermodynamic calculations can satisfy the needs of the calculation of the sequestration capacity in the temperature and pressure range for disposal of CO2 in deep saline aquifers.More experimental data and more accurate thermodynamic calculations are needed in high temperature and pressure ranges(above 398.15K and 31.5MPa).  相似文献   
106.
The properties of some well-characterized sodium linear decyldiphenylether (C10DPE)sulfonates have been studied. Among the properties investigated are dynamic and equilibrium surface tension, critical micelle concentration (CMC), area per molecule at the aqueous solution/air interface, wetting time by the Draves technique, foaming by the Ross-Miles method, solubilization, and hydrotropy. The decyldiphenylether moiety appears to be equivalent to a terminally substituted straight alkyl chain of 16 carbon atoms. The trialkyl- and dialkyl-mono-sulfonates have solubilities of < 0.01 g/dm3 in water, but are readily soluble in hexane. The didecyldiphenyl ether disulfonate (DADS) has a very low CMC value (1.0 × 10−5 mol dm−3) in aqueous 0.1 N Na+ solution (NaCl), characteristic of surfactants with two hydrophilic and two hydrophobic groups. It also has a much larger area per molecule at the aqueous solution/air interface than the monodecyldiphenyl-ether monosulfonate (MAMS) and a much higher surface tension at the CMC. MAMS has a much lower surface tension at a surface age of 1 second (γ1s) than either DADS or the monodecyldiphenylether disulfonate (MADS). In agreement with γ1s and γeq values, wetting times increase in the order: MAMS < DADS < MADS and initial foam heights decrease in the order: MAMS > DADS > MADS. Solubilization for three water-insoluble surfactants decreases in the order: DADS > MAMS > MADS, while hydrotropy is most pronounced with the disulfonates.  相似文献   
107.
针对多出救点多物资多目标应急调度问题的特点,并结合溢油敏感区等对响应时间的限制,提出了基于不同响应时间段的动态优化模型.以应急救援时间最早和出救点数目最少为优化目标,对不同响应时间段分别运用理想点法和构造剔除集合确定最优调度方案.最后通过算例验证了所提出调度方法的可行性.  相似文献   
108.
针对某水库重力坝坝基地层倾角平缓(8°~15°),基岩为薄层状结构,坝基深层抗滑设计是工程关键技术,在利用抗剪断强度理论进行坝基抗滑稳定计算的基础上,通过分析比较常见的坝基基础处理措施,最终确定重力坝坝基采用坝趾处设置混凝土深齿墙措施,可同时提高坝基浅层及深层抗滑稳定安全系数。  相似文献   
109.
本文从平衡判据的普遍规律--克劳修斯不等式出发,按照不同的过程条件,分别讨论了熵判据、亥氏函数和吉氏函数判据以及相变化和化学变化的可逆性判据.同时指出了这些平衡判据所包含的物理意义及它们间的一些内在联系.  相似文献   
110.
The acid-base equilibria of three anionic sulfonephthalein dyes, viz., bromothymol blue (BTB), thymol blue (TB), and cresol red (CR), were studied spectroscopically in aqueous media containing the water-soluble noninonic polymers polyvinyl alcohol (PVA) and polyethylene glycol (PEG) in the presence of an anionic surfactant, sodium dodecyl sulfate (SDS). A partition equilibrium method was used to determine the equilibrium constant of partition of the dyes between the micellar pseudo phase and aqueous phase in the presence of PVA and PEG. The critical aggregation concentrations (CAC) of the surfactants in buffered aqueous systems containing the neutral polymers were also determined. The CAC of the polymer-surfactant systems were found to be lower than the critical micelle concentration of such systems in the absence of polymer, in otherwise identical conditions. The pH-dependent association constants, K ass, of the sulfonephthalein dyes with the SDS-PVA system increased with the increase in molecular weight of the polymer. The interactions of the dyes with the buffered aqueous SDS-PVA and SDS-PEG systems were found to be endothermic and entropy oriented. In the polymer domain, the head group region of the micelles was more exposed at lower concentrations of the polymer, but under excess polymer concentration they were increasingly shielded, which impaired their electrostatic interaction with the dyes.  相似文献   
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