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991.
核电站放射性废液组成复杂,其中137Cs、90Sr和60Co是放射性废液处理的主要目标。 本文采用稳定同位素模拟放射性废液,研究了Cs+离子在强酸性阳离子树脂IRN97中的交换等温线、动力学特性以及固定床穿透行为,探讨了共存的硼酸和Sr2+、Co2+等核素离子对Cs+离子交换行为的影响。 结果表明,废液中存在的高浓度硼酸在一定程度上会减小树脂对Cs+的交换量;与共存的Sr2+和Co2+离子相比,虽然Cs+的交换速率快,但树脂对Sr2+和Co2+的选择性更高,因此在达到交换平衡状态下,Sr2+和Co2+的交换容量大于Cs+;在采用固定床吸附柱进行的动态吸附中,提高Cs+的进水浓度可以提高树脂的利用率。  相似文献   
992.
Because our earlier work indicated a strong correlation between specific antibody productivity and cell density in perfusion culture, we conducted experiments to determine the optimum means of increasing cell density while mainitaining high antibody productivity. The rates of medium supply and waste removal were varied to determine whether cell density was limited or inhibited, and whether a diffusable substance could be responsible for the correlation between antibody productivity and cell density. Nutrient supply was found to be a stronger determinant of cell density than waste removal; however, the rate of waste removal had a greater effect on cell growth at lower cell densities. Even at noninhibitory levels of ammonia and lactate, cellular metabolism was regulated to minimize their concentrations at lowered rates of waste removal. Separate step changes in glucose and glutamine resulted in increased cell density and antibody concentration. Specific antibody productivity increased following the step in glutamine, but not glucose. Both steps caused changes in cellular metabolism that prevented the levels of lactate and ammonia from reaching toxic levels.  相似文献   
993.
城市生活垃圾的燃烧特性   总被引:4,自引:1,他引:4  
选取城市生活垃圾中的九种典型级分进行热重特性试验,根据热失重曲线得出反应动力力学参数及反应速率控制方程,提出燃烧指数表征垃圾的燃烧特性。研究结果表明,垃圾中不同的组分的燃烧特性判别很大,不同的垃圾控制燃烧反应的过程是不同的,废塑料,废纸和废棉布类符合两段燃烧模型,且低温段的动力学参数E和A远大于高温段,其余六处组分可用一段模型来描述,计算得出的失重关系式能较好地反映垃圾燃烧的失重过程,挥 分高的垃  相似文献   
994.
采用气提吸附/热脱附/气相色谱-质谱法对齐鲁公司所处地区工业污水进行分析。方法采用Tenax-GC吸附剂对样品进行气提吸附,脱附时样品直接进入色谱仪汽化室,一次进样即可完成全组分分析,共检测出含四氯丙醚在内的40种有机组分,测定了各组分的程序升温保留指数。气相色谱-质谱法测定出四氯丙醚三个异构体的结构。  相似文献   
995.
快速准确分析处理过程中含油污泥的含水率和含油率有助于现场评价其原油回收效率和优化处理工艺参数。以Dean-Stark装置测定的含油污泥样品的含水率和含油率作为参考值,利用低场核磁共振结合偏最小二乘回归法建立了样品含水率和含油率校正集模型,考察了回波衰减曲线和横向弛豫时间T2曲线对校正集模型性能的影响。结果表明,采用前者建立的校正集模型性能优于后者;在此基础上,建立了31个样品的含水率和含油率通用校正集模型,其含水率和含油率模型的决定系数(R2)分别为0.965 7和0.978 5,校正标准差(RMSECV)分别为2.73%和2.22%。利用3个不同批次采集的HZ-OS样品对该模型进行验证,对于含水率和含油率模型,其验证集R2分别为0.914 1和0.924 7,预测标准差(RMSEP)分别为1.85%和2.04%,与RMSECV值比较接近,说明该模型的稳定性较好,可用于准确分析样品的含水率和含油率。  相似文献   
996.
Mushroom cultivation waste (MCW) is a polypropylene bag stuffed with wood flour and nutrients for growing mushroom, which is a feasible feedstock for anaerobic biohydrogen production owing to its abundant availability, high organic and nutrient content. This study optimized the seed inoculum from various waste sludges (sewage sludge, cow dung and pig slurry), nutrient addition and operation conditions (moisture content and MCW powder particle size) for maximal biohydrogen production by solid‐state fermentation (SSF). SSF batch test was operated at a MCW 3 g total volatile solid (TVS)/L, temperature 55 °C and rotation speed of 15 rpm with a vertical rotative shaker. The peak hydrogen production performance of hydrogen production rate (HPR) 9.50 mol H2/kg‐d and hydrogen yield (HY) 0.29 mmol H2/g TVS) are obtained using sewage sludge 2 seed inoculum, nutrients addition, moisture content 70 % and particle size of 1.190~0.590 mm. The results show that the MCW has the potential for hydrogen production by anaerobic mixed microflora using solid‐state fermentation. The bioenergy of 1842 kWh while using SSF to conver MCW to produce biohydrogen and it could reduce CO2 emission of 114–178 kg per year comparing using fossil fuel such as coal, fuel oil and natural gas.  相似文献   
997.
This paper presents a study of immiscible compressible two‐phase, such as water and gas, flow through double porosity media. The microscopic model consists of the usual equations derived from the mass conservation laws of both fluids, along with the standard Darcy–Muskat law relating the velocities to the pressure gradients and gravitational effects. The problem is written in terms of the phase formulation, that is, where the phase pressures and the phase saturations are primary unknowns. The fractured medium consists of periodically repeating homogeneous blocks and fractures, where the absolute permeability of the medium becomes discontinuous. Consequently, the model involves highly oscillatory characteristics. The major difficulties related to this model are in the nonlinear degenerate structure of the equations, as well as in the coupling in the system. We obtain the convergence of the solutions, and a macroscopic model of the problem is constructed using the notion of two‐scale convergence combined with the dilatation technique. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
998.
球形托卡马克堆嬗变中子学计算的比较研究   总被引:2,自引:0,他引:2  
基于对球形托卡马克(ST)聚变堆的研究,提出了ST聚变-嬗变堆的设计概念。运用一维输运燃耗计算程序BISON3.0进行了优化设计,确定了适合于嬗变少额锕系MA核素的堆芯等离子体参数、包层结构及合适的换料周期。在一维计算的基础上,运用二维中子学程序TWODANT进行了二维中子输运计算;结合TWODANT给出的中子通量,运用一维放射性计算程序FDKR进行了燃耗计算,并给出了有关的计算结果。  相似文献   
999.
Hachiya H  Ito S  Fushinuki Y  Masadome T  Asano Y  Imato T 《Talanta》1999,48(5):4196-1004
A continuous monitoring system for cyanide with a galvanic hydrogen cyanide sensor and an aeration pump for purging was developed. Hydrogen cyanide evolved from cyanide solution using a purging pump was measured with the hydrogen cyanide sensor. The system showed good performance in terms of stability and selectivity. A linear calibration curve was obtained in the concentrating range from 0 to 15 mg dm3 of cyanide ion with a slope of −0.24 μA mg−1 dm−3. The lower detection limit was 0.1 mg dm−3. The 90% response time of the sensor system was within 3.5 min for a 0.5 mg dm−3 cyanide solution, when the flow rate of the purging air was 1 dm3 min−1. The system maintained the initial performance for 6 months in the field test. The developed galvanic sensor system was not subject to interference from sulfide and residual chlorine, compared with a potentiometric sensor system developed previously. The analytical results obtained by the present system were in good agreement with those obtained by the pyridine pyrazolone method. The correlation factor and regression line between both methods were 0.979 and Y=2.30×10−4+1.12X, respectively. This system was successfully applied for a continuous monitoring of cyanide ion in waste water.  相似文献   
1000.
Medical waste has increased in the past 3 years as a result of the coronavirus disease 2019 (COVID-19) pandemic. This condition is expected to exacerbate due to the growing healthcare markets and aging population, posing health threats to the public via environmental footprints. To alleviate these impacts, there is an urgent need for medical waste management. This article highlights the drawbacks of current disposal methods and the potential of medical waste reuse and recycling, emphasizing the processes, materials, and chemistry involved in each practice. Further discussion is provided on the chemical and mechanical recycling of plastics as the dominating material in biomedical applications, and possible strategies and challenges in recycling and reusing biomedical materials are explored in this review.  相似文献   
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