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971.
In the present study, computational fluid dynamics (CFD) is used to investigate inspiratory and expiratory airflow characteristics in the human upper respiratory tract for the purpose of identifying the probable locations of particle deposition and the wall injury. Computed tomography (CT) scan data was used to reconstruct a three dimensional respiratory tract from trachea to first generation bronchi. To compare, a simplified model of respiratory tract based on Weibel was also used in the study. The steady state results are obtained for an airflow rate of 45 L/min, corresponding to the heavy breathing condition. The velocity distribution, wall shear stress, static pressure and particle deposition are compared for inspiratory flows in simplified and realistic models and expiratory flows in realistic model only. The results show that the location of cartilaginous rings is susceptible to wall injury and local particle deposition. 相似文献
972.
For a non-compact, complete and simply connected manifoldM without conjugate points, we prove that if the determinant of the second fundamental form of the geodesic spheres inM is a radial function, then the geodesic spheres are convex. We also show that ifM is two or three dimensional and without conjugate points, then, at every point there exists a ray with no focal points on
it relative to the initial point of the ray. The proofs use a result from the theory of vector bundles combined with the index
lemma. 相似文献
973.
An identity orientation of a graph G=(V,E) is an orientation of some of the edges of E such that the resulting partially oriented graph has no automorphism other than the identity. We show that the complete bipartite graph Ks,t, with st, does not have an identity orientation if t3s-log3(s-1). We also show that if (r+1)(r+2)2s then Ks,3s-r does have an identity orientation. These results improve the previous bounds obtained by Harary and Jacobson (Discuss. Math. - Graph Theory 21 (2001) 158). We use these results to determine exactly the values of t for which an identity orientation of Ks,t exists for 2s17. 相似文献
974.
Investigation of experimental observables in search of the chiral magnetic effect in heavy-ion collisions in the STAR experiment
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Subikash Choudhury Xin Dong Jim Drachenberg James Dunlop ShinIchi Esumi 冯毅程 Evan Finch 胡昱 Jiangyong Jia Jerome Lauret Wei Li 廖劲峰 林裕富 Mike Lisa Takafumi Niida Robert Lanny Ray Masha Sergeeva 申迪宇 施舒哲 Paul Sorensen 唐爱洪 Prithwish Tribedy Gene Van Buren Sergei Voloshin 王福强 王钢 徐浩洁 徐之湾 Nanxi Yao 赵杰 《中国物理C(英文版)》2022,46(1):014101-014101-17
The chiral magnetic effect(CME)is a novel transport phenomenon,arising from the interplay between quantum anomalies and strong magnetic fields in chiral systems.In high-energy nuclear collisions,the CME may survive the expansion of the quark-gluon plasma fireball and be detected in experiments.Over the past two decades,experimental searches for the CME have attracted extensive interest at the Relativistic Heavy Ion Collider(RHIC)and the Large Hadron Collider(LHC).The main goal of this study is to investigate three pertinent experimental approaches:the$\gamma$correlator,the R correlator,and the signed balance functions.We exploit simple Monte Carlo simulations and a realistic event generator(EBE-AVFD)to verify the equivalence of the core components among these methods and to ascertain their sensitivities to the CME signal and the background contributions for the isobar collisions at the RHIC. 相似文献
975.
Paul Dipayan Mahanta Saurov Tag Hui Das Sanjib Kumar Das Gupta Debmalya Tanti Bhaben Ananthan Rajendran Das Ranjan Jambhulkar Sanjay Hui Pallabi Kalita 《Molecular diversity》2022,26(4):1933-1955
Molecular Diversity - Breast and stomach cancer is reported as a leading cause for human mortality across the world. The overexpression of receptor tyrosine kinase (RTK) proteins, namely the human... 相似文献
976.
Indranil Chakrabarty Sovik Roy Nirman Ganguly Binayak S. Choudhury 《International Journal of Theoretical Physics》2009,48(6):1833-1840
In this work we describe a protocol by which two of three parties generate two bipartite entangled state among themselves
without involving third party, from a non maximal W-state or W-type state |X〉=α|001〉123+β|010〉123+γ|100〉123,α
2+β
2+γ
2=1 shared by three distant partners. Also we have considered the case β=γ, to obtain a range for α
2, for which the local output states are separable and non local output states are inseparable. We also find out the dependence
of the mixedness of inseparable states with their amount of inseparability, for that range of α
2. 相似文献
977.
RK Choudhury 《Pramana》2001,57(2-3):585-600
Nuclear fission process involves large scale shape changes of the nucleus, while it evolves from a nearly spherical configuration
to two separated fission fragments. The dynamics of these shape changes in the nuclear many body system is governed by a strong
interplay of the collective and single particle degrees of freedom. With the availability of heavy ion accelerators, there
has been an impetus to study the nuclear dynamics through the investigations of nucleus-nucleus collisions involving fusion
and fission process. From the various investigations carried out in the past years, it is now well recognized that there is
large scale damping of collective modes in heavy ion induced fission reactions, which in other words implies that nuclear
motion is highly viscous. In recent years, there have been many experimental observations in heavy ion induced fission reactions
at medium bombarding energies, which suggest possible occurrence of various non-equilibrium modes of fission such as quasi-fission,
fast fission and pre-equilibrium fission, where some of the internal degrees of freedom of the nucleus is not fully equilibrated.
We have carried out extensive investigations on the fission fragment angular distributions at near barrier bombarding energies
using heavy fissile targets. The measured fragment anisotropies when compared with the standard saddle point model (SSPM)
calculations show that for projectile-target systems having zero or low ground state spins, the angular anisotropy exhibits
a peak-like behaviour at the sub barrier energies, which cannot be explained by the SSPM calculations. For projectiles or
targets with large ground state spins, the anomalous peaking gets washed out due to smearing of the K-distribution by the intrinsic entrance channel spins. Recently studies have been carried out on the spin distributions of
fission fragments through the gamma ray multiplicity measurements. The fission fragments acquire spin mainly from two sources:
(i) due to rigid rotation of the nascent fragments at scission and (ii) due to statistical excitation of the spin bearing
collective modes in the fissioning nucleus. One of the collective modes — the tilting mode depends on the K quantum number and is responsible for the emission angle dependence of fragment spin. In our studies, we have shown conclusively
that the collective statistical spin modes get strongly suppressed for high K values corresponding to large rotational frequencies along the fission axis. These results bring out the importance of the
dynamical effects in the heavy ion induced fusion-fission reactions. The present article will review the work carried out
on the above aspects in heavy ion fission reactions as well as on the fission time scales, and some of the recent studies
on the mass-energy correlations of fission fragments at near-barrier bombarding energies. 相似文献
978.
Adcox K Adler SS Ajitanand NN Akiba Y Alexander J Aphecetche L Arai Y Aronson SH Averbeck R Awes TC Barish KN Barnes PD Barrette J Bassalleck B Bathe S Baublis V Bazilevsky A Belikov S Bellaiche FG Belyaev ST Bennett MJ Berdnikov Y Botelho S Brooks ML Brown DS Bruner N Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy J Butsyk S Carey TA Chand P Chang J Chang WC Chavez LL Chernichenko S Chi CY Chiba J Chiu M Choudhury RK Christ T Chujo T Chung MS Chung P Cianciolo V Cole BA D'Enterria DG 《Physical review letters》2001,87(5):052301
979.
Dambarudhar Mohanta Fouran Singh D. K. Avasthi Amarjyoti Choudhury 《Central European Journal of Physics》2006,4(2):187-195
Semiconductor nanoparticles (CdS) were fabricated by an inexpensive chemical route using polyvinyl alcohol (PVA) as the dielectric
host matrix. Nano-CdS in PVA were subjected to ion irradiation (using oxygen, chlorine and gold) in the medium energy range
(80–100 MeV) and under fluence variation of 1011–1013 ions/cm2. The nature of light emission was found to be drastically different in each of the three cases. Photoluminescence spectra
of oxygen irradiated samples exhibit band edge emission (2.8 eV) as well as trap related emission (1.76 eV) whereas band edge
emission is found to be bleached out for chlorine ion irradiated nano-CdS. The intense broad PL peaks, noticeable in the case
of gold ion irradiated samples suggest superposition of the two peaks — namely, band edge emission and trap related emission.
Furthermore, in the case of gold ion irradiated nano-CdS, energy shift in the PL spectra reveals variation in size distribution
caused by the extra pressure effect of heavy gold ion beams. The mechanism of such a difference as a result of ion irradiation-type
and ion-fluence is discussed in detail. 相似文献
980.
S Sundar Manoharan Ranjan K SahuD Elefant C.M Schneider 《Solid State Communications》2003,125(2):103-106
We observe a sharp increase in negative magneto-resistance ratio up to 40% for x=0.1, in La0.5Sr0.5Co1−xRuxO3 which is due to the magnetic disorder induced by an anti-ferromagnetic interaction between Co and Ru ions. We also observe a metal to insulator and a ferromagnetic to anti-ferromagnetic transition for 0≤x≤0.3. Ruthenium (IV) ion disrupts an intermediate spin state of cobalt (Co3+:t2g5eg1), forcing a double exchange mediated ferromagnetic state to an anti-ferromagnetic spin state for x≥0.2. 相似文献