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71.
The implantation of chlorine and subsequent annealing is found to reduce the hopping conductivity of amorphous germanium, thereby indicating the removal of states in the gap. The photoconductivity remains very low, which implies that the gap states are still numerous. 相似文献
72.
This paper studies the use of multicast together with proxy nodes for reliably disseminating data from a single source to a large number of receivers. In order to achieve reliability, data must be retransmitted in case of loss either by the source or by special network nodes, called proxies. Each proxy is responsible for reliably delivering the data to a subgroup it is assigned. The multicast tree is partitioned into subgroups that form a hierarchy rooted at the source, hence the term hierarchical reliable multicast. The performance of this approach strongly depends on the topology and the loss characteristics of the underlying tree and the location of proxies. In the first part of the paper, we study the processing and bandwidth performance of such a reliable multicast dissemination given the tree and the placement of proxies. In the second part of the paper, we develop dynamic programming algorithms that give a placement of a fixed number of proxies on an arbitrary tree that minimizes the bandwidth used for reliable transfer. The first algorithm provides an optimal solution to the multicast proxies location problem in polynomial time, in the number of nodes and proxies. The second is an approximation algorithm that gives a solution with cost within a chosen precision from the optimal, in an improved running time. An optimal and an approximate solution are also provided for the proxies location problem if unicast is used for transmissions. Applications of this dynamic programming approach to related problems are discussed. 相似文献
73.
The spatial distribution of the power transfer achieved by contradirectional two-beam coupling using self-pumped photorefractive reflection gratings is investigated in two materials with different photorefractive gain coefficients, LiNbO3:Fe and KNbO3:Fe. Incremental portions of the volume grating are erased optically by inducing thin optical damage planes, reducing the overall two-beam coupling efficiency. By monitoring the effect of local grating disruption, the distribution of power transfer is spatially resolved throughout the crystal, and the results are found to be in agreement with our theoretical predictions. 相似文献
74.
The origin of the main electron trap (0.83 eV) in GaAs is investigated by creating conditions to favour the formation of Ga-vacancy-oxygen complex in the material. Two specific schemes have been used, (1) Liquid phase epitaxial (LPE) growth of the material at high temperatures (≈1000°C) with oxygen doping and (2) Electron bombardment of LPE material and subsequent annealing. The traps have been characterised by transient capacitance technique. The results show that the main electron trap cannot be produced by either of the schemes thereby implying that a complex involving Ga-vacancy and oxygen may not be responsible for the trap. 相似文献
75.
76.
Pragyan Paramita Vimala Devi Subramaniam Ramachandran Murugesan Madhumala Gopinath Ilangovan Ramachandran Satish Ramalingam Xiao Feng Sun Antara Banerjee Francesco Marotta Surajit Pathak 《IET nanobiotechnology / IET》2018,12(6):727
Research dealing with early diagnosis and efficient treatment in colon cancer to improve patient''s survival is still under investigation. Chemotherapeutic agent result in high systemic toxicity due to their non‐specific actions on DNA repair and/or cell replication. Traditional medicine such as Lycopodium clavatum (LC) has been claimed to have therapeutic potentials against cancer. The present study focuses on targeted drug delivery of cationic liposomal nanoformulated LC (CL‐LC) in colon cancer cells (HCT15) and comparing the efficacy with an anti‐colon cancer drug, 7‐ethyl‐10‐hydroxy‐camptothecin (SN38) along with its nanoformulated form (CL‐SN38). The colloidal suspension of LC was made using thin film hydration method. The drugs were characterised using ultraviolet, dynamic light scattering, scanning electron microscopy, energy, dispersive X‐ray spectroscopy. In vitro drug release showed kinetics of 49 and 89% of SN38 and LC, whereas CL‐SN38 and CL‐LC showed 73 and 74% of sustained drug release, respectively. Studies on morphological changes, cell viability, cytotoxicity, apoptosis, cancer‐associated gene expression analysis of Bcl‐2, Bax, p53 by real‐time polymerase chain reaction and western blot analysis of Bad and p53 protein were performed. Nanoformulated LC significantly inhibited growth and increased the apoptosis of colon cancer cells indicating its potential anti‐cancer activity against colon cancer cells.Inspec keywords: cancer, biological organs, cellular biophysics, drug delivery systems, drugs, nanomedicine, genetics, DNA, molecular biophysics, biochemistry, lipid bilayers, toxicology, suspensions, colloids, light scattering, X‐ray chemical analysis, solvation, enzymes, nanostructured materialsOther keywords: energy dispersive X‐ray spectroscopy, in vitro drug release, morphological changes, cell viability, cytotoxicity, apoptosis, cancer‐associated gene expression analysis, Bcl‐2, Bax, real‐time polymerase chain reaction, western blot analysis, Bad protein, p53 protein, scanning electron microscopy, dynamic light scattering, ultraviolet scattering, thin film hydration method, colloidal suspension, nanoformulated form CL‐SN38, 7‐ethyl‐10‐hydroxy‐camptothecin, anticolon cancer drug, colon cancer cells HCT15, cationic liposomal nanoformulated LC, targeted drug delivery, therapeutic potentials, Lycopodium clavatum, traditional medicines, cell replication, DNA repair, nonspecific actions, high systemic toxicity, chemotherapeutic agents, patient survival, colon cancer treatment, colon cancer diagnosis, CL‐LC, potential anticancer activity 相似文献
77.
In this paper, a simple single variable shear deformable nonlocal theory for bending of micro- and nano-scale rectangular beams is presented. To incorporate small size effects, the theory uses Eringen’s nonlocal differential constitutive relations. The theory has only one fourth-order governing differential equation involving a single unknown variable. The governing equation and the expressions for the bending moment and shear force of the present theory are strikingly similar to those of nonlocal Euler-Bernoulli Beam Theory (EBT) formulated based on Eringen’s nonlocal elasticity theory. The theory assumes that the axial and lateral displacements have bending and shear components such that the bending components do not contribute towards shear force, and the shear components do not contribute towards bending moment. Also, the chosen displacement functions of the theory give rise to a realistic parabolic transverse shear stress distribution across the beam cross-section. Efficacy of the proposed theory is demonstrated through bending of simply supported, cantilever and clamped-clamped micro- and nano-scale beams of rectangular cross-section. The numerical results obtained by using the present theory are compared with those predicted by other nonlocal first-order and higher-order shear deformation beam theories. The results obtained are quite accurate. 相似文献
78.
Sravani K. Girija Prathyusha D. Gopichand Ch. Maturi Surya Manoj Elsinawi Ameen Guha Koushik Rao K. Srinivasa 《Microsystem Technologies》2022,28(4):913-928
Microsystem Technologies - This paper presents the design a capacitive shunt type RF-MEMS switch with high isolation, high switching speed and low actuation voltage for Ka-band applications. The... 相似文献
79.
Phase equilibria in the binary system Bi2O3-ZnO were studied by quenching technique. Heat-treated compositions were subjected to X-ray diffraction for phase identification, and differential thermal analysis, optical and scanning electron microscopy were used to determine the solid-liquid equilibria occurring in this system. The data thus obtained revealed that incorporation of a small amount of ZnO to the high-temperature face-centered cubic lattice of Bi2O3 leads to the formation of a body-centered cubic solid solution (-Bi2O3), which extends up to a composition of 2.2 mol% ZnO at a temperature near 750°C. On cooling, the -Bi2O3 solid solution undergoes a eutectoid transformation at a temperature of 710°C to yield the low-temperature monoclinic polymorph of Bi2O3 (-Bi2O3) and Bi38ZnO58. The eutectoid occurs at a composition of 1.8 mol% ZnO. The compound Bi38ZnO58 has a crystal structure analogous to the body-centered cubic -Bi2O3 solid solution and melts incongruently at a temperature near 753 ± 2°C to yield -Bi2O3 and liquid. A binary eutectic occurs between Bi38ZnO58 and ZnO at a composition near 25 ± 1.0 mol% ZnO with a melting temperature of 738 ±2°C. Based on the data obtained in this study, a revised phase diagram of the binary system Bi2O3-ZnO is proposed. 相似文献
80.
Obiora Valentine Saha Chitta Bazi Ammar Al Guha Koushik 《Microsystem Technologies》2021,27(8):3161-3169
Microsystem Technologies - This paper presents a critical analysis of the meta-heuristic techniques used in various researches on the optimisation of photovoltaic (PV) parameters, which involves... 相似文献