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991.
Zusammenfassung 2-Oxo-1-pyrrolidin-essigsäure-Derivate lassen sich weder UV-spektroskopisch, colorimetrisch noch fluorimetrisch bestimmen, GC-Bestimmungen sind nur bedingt anwendbar. Zur Bestimmung von 2-Oxo-1-pyrrolidin-essigsäure, deren Amid, Hydrazid sowie 1,2-Bis(2-oxo-pyrrolidin-1-essigsäure)-hydrazid bzw. ,-Bis(2-oxo-1-pyrrolidinacetamido)-alkanen in biologischem Material eignet sich die Extraktion der gefriergetrockneten Analysenproben mit Chloroform/Methanol-Gemischen, Dünnschicht-Chromatographie auf Kieselgel und Detektion mit verschiedenen Sprühreagentien. Durch Flächengrößenvergleich/Scannen sind Bestimmungen aus Vollblut, Plasma, Organhomogenaten und Urin möglich. Die Anwendbarkeit der Methode wird am Beispiel von Stabilitätsprüfungen in biologischem Material, Resorptionsnachweisen, Plasma- und Urinspiegeln bei Ratten, Hunden und Menschen demonstriert.
Contribution to the determination of 2-oxo-pyrrolidine derivatives in biological material
Summary Determination of 2-oxo-1-pyrrolidine-acetic acid derivatives cannot be carried out either spectroscopically, colorimetrically or fluorimetrically, and GC determination is only conditionally suitable. For the determination of 2-oxo-1-pyrrolidine-acetic acid, its amide, hydrazide as well as 1,2-bis (2-oxo-pyrrolidine-1-acetic acid)-hydrazide and ,-bis(2-oxo-1-pyrrolidine-acetamido)-alkanes in biological material, a suitable method is the extraction of freeze-dried analytical samples with chloroform/methanol mixtures, TLC on silica gel and detection with various spray reagents. Determinations from whole blood, plasma, organ homogenates and urine are possible by spot area comparison or scanning. The practicability of the method is demonstrated with the example of stability tests in biological material, proof of absorption, and determination of plasma and urine levels in rats, dogs and in man.
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992.
Thermo-mechanical reliability concerns in microelectronics and microsystem technology have led to a significant need in information on stress/strain behavior inside microscopic components under load. Because of the decreasing size of structures new measurement tools have to be developed in order to assure future experimental access. Strain measurement from load state micrographs utilizing correlation techniques seems to be one of the promising approaches. Its application to thermally stressed objects in electronics packaging is the main topic of this paper. Deformation measurements are presented for solder interconnects of flip chip and chip scale packages. Emphasis is made for the experimental support of finite element simulation by means of experimental validation of mechanical modeling. Furthermore, a wide variety of new packaging materials and material compounds are to be characterized. Different material properties for bulk material and microscopic structures intensify the search for new testing methods. Again correlation algorithms can be applied to measure strains on microscopic areas and subsequently to obtain material properties. The feasibility to measure coefficients of thermal expansion and Poisson ratios on tiny specimens is demonstrated in the paper.  相似文献   
993.
This study was designed to investigate objective voice quality measurements in unilateral vocal fold paralysis (UVFP) by eliminating intersubject variability. To our knowledge this is the first report objectively analyzing paralytic dysphonia as compared to the same voice before onset of UVFP. The voices of two male subjects were prospectively recorded before and after the onset of iatrogenic UVFP (thoracic surgery).The following acoustic measurements of the vowel /a/ were performed using the CSL and MDVP (Kay Elemetrics): jitter, shimmer, harmonics-to-noise ratio, cepstral peak prominence, the relative energy levels of the first harmonic, the first formant and the third formant, the spectral slope in the low-frequency zone (0-1 kHz and 0-2 kHz), and the relative level of energy above 6 kHz. Distribution of spectral energy was analyzed from a long-term average spectrum of 40 seconds of text. Laryngeal aerodynamic measurements were obtained for one patient before and after onset of paralysis using the Aerophone II (Kay Elemetrics). Pitch and amplitude perturbation increased secondary to UVFP, while the harmonics-to-noise ratio and the cepstral peak prominence decreased. A relative increase in the mid-frequency and high-frequency ranges and a decrease in the low-frequency spectral slope were observed. Mean airflow rate and intraoral pressure increased, and glottal resistance and vocal efficiency decreased secondary to UVFP. The findings of this self-paired study confirm some but not all the results of previous studies. Measures involving the fundamental and the formants did not corroborate previous findings. Further investigation with vocal tract modeling is warranted.  相似文献   
994.
Ingo R. Titze   《Journal of voice》2001,15(4):519-528
Resonant voice, often described in terms of vibratory sensations in the face, is investigated acoustically by calculating vocal tract inertance. It appears that the ease of production and vibrancy of resonant voice depends more on lowering phonation threshold pressure than on tissue or air resonance in or around the face. Phonation threshold pressure is lowered by increasing air column inertance in the laryngeal vestibule. The fact that the sensations are felt in the face is an indication of effective conversion of aerodynamic energy to acoustic energy, rather than sound resonation in the sinuses or the nasal airways.  相似文献   
995.
First of all the deformation is considered of two infinitesimal material line elements lying along vectors M,N emanating from a particle at X in a body. For all M,N lying in a given plane, an identity is derived relating the stretches along M,N and the angles of the pair of infinitesimal material line elements before and after deformation. Then, the deformation is considered of three non-coplanar infinitesimal material line elements lying along vectors M,N,P emanating from a particle at X in a body. An identity is derived relating the stretches along M,N,P and the angles between the three pairs of infinitesimal material line elements before and after deformation. The identity is factored leading to easy interpretation. The special case of infinitesimal strain is considered.   相似文献   
996.
杨招伟  卢文波  陈明  严鹏  胡英国  刘美山  吴新霞  冷振东 《爆炸与冲击》2020,40(6):065202-1-065202-10

爆破地震波传播衰减研究对爆破振动预测及安全控制有着重要的指导意义。针对爆破振动实测信号,结合P波、S波的初至识别结果,计算P波、S波在岩体中的传播速度及P波的上升时间,进一步得出岩体介质P波品质因子。结合现场实测振动数据,计算丰宁抽水蓄能电站及舟山绿色石化基地试验区域内岩体介质P波品质因子,计算结果分别为19.02和14.07。结果表明,通过实测地表爆破振动计算得到的P波品质因子远小于经验公式的计算值及一般原岩的品质因子,说明地表疏松层对爆破地震波的传播衰减有较大影响。

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997.
丁燕红  李明吉  杨保和  马叙 《物理学报》2011,60(9):97502-097502
研究了退火温度对Fe15.38Co61.52Cu0.6Nb2.5Si11B9纳米晶软磁合金交流磁性的影响,并且分析了获得较好软磁性能的可能原因.合金的电阻率随着退火温度的增加逐渐降低.μ'f0值与饱和磁化强度Ms之间没有明显的正比关系,合金的旋磁比γ随退火温度的升高应呈不规则的 关键词: 纳米晶合金 软磁材料 品质因数 热处理  相似文献   
998.
无机化学实验是高校一门重要的基础实验课程。本文介绍在无机化学实验课程中运用启发式教学法,并将其贯穿于整个教学过程。采用多种途径鼓励学生进行实践创新,引导学生深入思考,在实验中发现、探究和解决问题,提高学生的综合素质。  相似文献   
999.
The recent Joint Commission on Accreditation of Healthcare Organization (JCAHO) requirement that hospital accreditation be based upon a Total Quality Management (TQM) approach has focused the attention of health care administrations on the use of techniques such as control charts. However, control charts are not typically adjusted for severity of illness. This adjustment is needed because, unlike industrial organizations, hospitals are not able to control all of their inputs and must accept variances in their patients. In this paper, we present a methodology for adjusting a health care organization's control charts to reflect their patient population's severity of illness during different time intervals. We then demonstrate that risk-adjusting expected patient outcomes can change our assessments of the relative quality of care offered by a health care organization in different time periods.  相似文献   
1000.
国内主要城市空气质量统计分析   总被引:1,自引:0,他引:1  
我国目前评价城市空气质量所用的空气污染指数法中仅以首要污染指数来反映空气质量状况,而忽视了次要污染物对空气质量的影响,这将会使评价结果的准确性产生偏差.本文在空气污染指数模型的基础上引入次要污染物,建立了新的空气质量评价模型,再利用该模型对我国近三年主要城市空气质量状况进行了评价及分析.  相似文献   
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