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41.
42.
G. V. Kotelnikov Sophia P. Moiseyeva E. V. Mezhburd E. I. Maevsky Elena V. Grishina 《Journal of Thermal Analysis and Calorimetry》2005,81(2):255-259
Summary Measurements of energy transformation in mitochondria are done on a capillary differential titration calorimeter CTD2156. It is important to mention that a sediment is quickly formed by the mitochondria suspension without mixing by means of a vibrating needle. During the measurements, the vibrating needle is located inside the working volume of the chamber. The design of the calorimeter is substantiated theoretically. It provides a new mode of a reagent input in the measuring volume of the calorimetric chambers. It expands the spectrum of tasks that can be solved using this instrument. In the capillary calorimeter the calorimetric chambers unit is simple and small in size. These advantages of capillary chambers provide an opportunity to unite 20 capillary calorimetric chambers in one calorimetric block. It allows designing a multi-channel titration calorimeter. There are obvious advantages of such a calorimeter over other instruments in screening researches and in researches of objects maintaining stability only for a short time. 相似文献
43.
F. Herbut 《Foundations of Physics Letters》1996,9(5):437-446
Bohr's well-known claim that only a registered phenomenon is a true phenomenon is further elaborated into occurrence in the past: If ideal occurrence of an eventP ((1–P)) is a state at a timet
i makes another eventQ ((1–Q))certain at a later timet
f, and, finallyU is the evolution operator fromt
i tot
f, then, it is proved that the final collapsed stateQ(U U
+)Q/TrQU U
+, which comes about in ideal occurrence ofQ att
f,equals the initial collapsed stateU(P P/TrP)U
+, which evolves from the state resulting from the ideal occurrence ofP in att
i. Utilizing the latter state is called theretroactive apparent ideal occurrence (RAIO) ofP in. A number of consequences, including the general notion of twin events (the case whent
f=t
i, andU=1) is derived. It is pointed out that RAIO is relevant in second-kind quantum measurement, in Wheeler's delayed-choice experiments in second-kind (or conditional) quantum preparators. 相似文献
44.
The quality of colour changes of the indicators hematoxylin, 4(2-pyridylazo)resorcinol (PAR), xylenol orange, pyrocatechol violet, chromazurolS and eriochrome cyanineR in the complexometric titration of copper(II) with ethylenediaminetetraacetic acid (EDTA) were studied with the help of tristimulus colorimetry, utilising a comparative study of the parameters SCD (specific colour discrimination), CIE La*b* 1976 and LABHNU 1977. Hematoxylin was found to be the best indicator among those studied. A screened indicator, viz. PAR + malachite green (52), was developed to enhance the quality of colour transition at the end-point and the accuracy of the titrimetric determination. 相似文献
45.
We propose a new approach for high-throughput continuous titration based on a flow ratiometry. The method was applied to potentiometric titrations of acids and bases. A base solution, the flow rate FB of which was varied in response to controller output voltage Vc, was merged with an acid solution under constant total (acid + base) flow rate. Downstream, the pH of the mixed solution was measured with a flow-through glass electrode. Initially, Vc, and thus FB was increased linearly. At the instant the equivalence point (EP) was sensed, the ramp direction of Vc was reversed from upward to downward. The direction was reversed to upward when EP was sensed again. Such the feedback-based operation gives a triangular waveform of Vc, because there is a delay corresponding mainly to the transit time of merged solutions to reach the sensor. The value of Vc that gives EP composition, VE, was estimated by averaging the most recent maximum and minimum values of Vc. Next, fixed triangular waves of Vc was used to control FB. The amplitude and the scan rate of the waves were fixed narrower and faster, respectively, than those in the feedback-based operation in order to improve the throughput rate. The EP can be located as long as the scan range covers VE. These automated processes limited the titration to just the narrow range around EP, and thus realized extremely high throughput rate of maximally 17.6 titrations per minute (=3.4 s per titration) at R.S.D. = 0.35%. 相似文献
46.
47.
48.
Peter-Th. Wilrich 《Accreditation and quality assurance》2007,12(5):231-240
Interlaboratory experiments often contain results that strongly deviate from other results obtained in the same laboratory
under repeatability conditions, or laboratory means that strongly deviate from other laboratory means. In ISO 5725-2 [1] and IUPAC [2], the basic standards for the organisation and analysis of interlaboratory experiments for the determination of precision
of a measurement method, outlier tests are performed in order to detect such situations and to finally decide whether these
values are retained in the analysis or discarded as outliers. This outlier treatment, which always has a subjective aspect,
becomes unnecessary by using robust estimates of the repeatability and reproducibility standard deviation. This paper proposes
to use Rousseeuw’s Q
n as an extremely robust and efficient estimate of the standard deviation. Two examples show the performance of the new method. 相似文献
49.
本文提出了碘量法滴定Ba-K-Bi-O和Ba-K-Pb-O氧化物中Ba和Pb的名义价态,然后据此计算这些氧化物中K和Ba含量的方法。该法适用于正常条件下合成的具有ABO3型钙钛矿结构的Ba-K-Bi-O和Ba-K-Pb-O晶体。用本法的滴定结果表明,Tc为31K的Ba-K-Bi-O超导体的K含量为0.4,当K含量减少时,Tc随之下降。 相似文献
50.