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1.
Professional psychologists are increasingly likely to encounter opportunities to work with patients and families facing end-of-life issues. Psychologists can provide psychological assessment, intervention for patients and families, consultation with and support of health care team members, grief therapy, and program development and evaluation. Psychological services are useful for healthy individuals who wish to make thoughtful plans about their own future care, patients with life-limiting illnesses, families stressed by providing end-of-life care, bereaved individuals, and health care providers who face issues of burnout and strain. Several challenges for psychologists working in end-of-life care are noted, including training, development of clear roles, and reimbursement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Samples were prepared by addition of a fluorinated poly(aryl ether ketone) (12F-PEK) to a commercial epoxy resin and curing at either 24 °C or 70 °C. The concentrations of fluoropolymer in the samples were 0, 5, 10, 20, 30, 40, and 50%. Phase inversion facilitates the formation of more and more smooth surfaces for scratch testing with increasing fluoropolymer concentration. A progressively increasing load from 0.03 N to 12 N was administered with a diamond tip to the surfaces of the samples; depths were determined within ±7.5 nm. The original scratch depth is a function of the fluoropolymer concentration. Scratch recovery (healing) reaches values up to 95%. Plots of the residual depth versus concentration of the fluoropolymer at 4, 6, 8, and 10 N reveal minima for all forces and both temperatures. Addition of only 5% or 10% 12F-PEK improves the scratch recovery significantly. The results are explained by changes of material morphology with the fluoropolymer concentration. Electronic Publication  相似文献   
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Electrochromic properties of electrochemically deposited and etched (EDE) WO3−x films have been investigated using voltammetry and nanogravimetry to elucidate the amount of residual stress associated with lattice polarization and deformation in WO3−x nanoparticles. The cathodic WO3−x deposition from pertungstic acid solution and unusual properties of the cathodic electroetching of the oxide in tetraethyl ammonium chloride solution are reported and elucidated on the basis of Electrochemical Quartz Crystal Nanogravimetry (EQCN) measurements. The stress enhanced resonant frequency shift was observed upon WO3−x film coloration. However, the stress enhancement appeared to be much lower (up to 4-6 times) than that measured for films synthesized by other methods. The stress reduction in WO3−x films under study has been attributed to the stress relaxing propensity of EDE film to suppress the compressive stress wave. A considerable isotopic effect has been observed in nanogravimetry of the H+ and D+ ion intercalation into WO3−x films. We have found that the isotopic effect is primarily due to the true mass loading difference between hydrogen and deuterium ions, for the same concentration of color centers (2.65 × 1021 cm−3), since EQCN frequency shifts associated with stress in the film for H+ and D+ are very close to each other.  相似文献   
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We have investigated transverse continuous wave NMR in a geometry where the modes are influenced by susceptibility anisotropy. The helium sample is separated by mylar foils into layers 12 m thick perpendicular to the external dc magnetic field. In this geometryl is constrained to be parallel to the field andd switches from parallel to perpendicular to the field over a small range of field around the dipole unlocking field. The mode frequencies below this critical field yield a value for the susceptibility anisotropy. Above the critical field the expected negative frequency shift is observed, as well as a positive frequency shift due to bulk material and an unexpected signal close to the Larmor frequency.  相似文献   
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We present preliminary measurements of the dynamics of a moving A-B phase interface in superfluid 3 He at temperatures below 0.2T c We initially stabilise the interface at low temperatures with a shaped magnetic field. We can then move the interface in a controlled manner by applying small additional time-dependent fields. The interface is created inside a quasiparticle radiator consisting of a cylindrical chamber in weak thermal contact with the refrigerant. Vibrating wire resonators inside the radiator allow us to monitor the temperature of the superfluid and to infer the heat generated by the interface motion. When we oscillate the interface at low frequencies, we measure spectacular oscillatory swings of the liquid temperature arising from the enormous change in the low lying density of states as the volume of the A-phase superfluid is alternately compressed and expanded. We have also observed hysteresis in the transition as a function of magnetic field. In particular, we observe a small history-dependent super-magnetisation of the B-phase prior to A-phase nucleation in the experimental chamber. When the system is in the metastable super-magnetised state we are able to observe a higher nucleation probability of the A-phase when the cryostat is exposed to neutrons.  相似文献   
8.
STUDY DESIGN: This study evaluates and compares the stiffness of two cervical spine fixation techniques. OBJECTIVES: This biomechanical study was carried out to compare the interspinous and Dewar cervical spine fixation techniques. SUMMARY OF BACKGROUND DATA: Interspinous wiring is a commonly used method of fixation in the cervical spine. The Dewar technique is less commonly known and practiced, and clinical experience has suggested that it may be a more stable technique. METHODS: Cervical spine specimens stabilized with the interspinous and "Dewar" techniques were biomechanically tested in flexion and in torsion. Stiffness and energy absorption under moderate loads were compared. The Dewar technique uses contoured double corticocancellous iliac grafts as internal grafts/splints fixed to the spine with threaded pins and wire. The interspinous technique is a single interspinous wire loop. Eleven fresh human cervical spines were harvested from cadavers. The spines were destabilized at C4-C5 by sectioning all tissue except the anterior longitudinal ligament. Each fixation technique was applied alternatively and tested on each spine. RESULTS: In torsion testing (n = 5), the Dewar fusion was 61% stiffer than the interspinous technique (P < 0.02). Dewar: 11.3 N/mm (s.d. 4.9 N/mm) and interspinous: 8.4 N/mm (SD 3.3 N/mm). In flexion testing (n = 6), the Dewar technique was 35% stiffer than the interspinous technique (P < 0.10). Dewar: 655.4 Nmm/degree (SD 293 Nmm/degree) and interspinous: 406.8 Nmm/degree (SD 113.0 Nmm/degree). Energy absorption with the interspinous technique was greater in flexion (P < 0.10) and in torsion (P < 0.005), indicating more deformation with the interspinous technique. There was no statistically significant difference between the means of specimens tested first and those tested second independently of the fixation technique. CONCLUSIONS: These tests indicate that the Dewar cervical spine fixation is stiffer than the single interspinous wire in both flexion and particularly torsion. This project is the only biomechanical study of the Dewar technique that we are aware of, and the results support the clinical findings regarding the effectiveness of this technique.  相似文献   
9.
No Heading We have measured responses of vibrating wire resonators in superfluid 4He at millikelvin temperatures. We find evidence for turbulence generation above a critical velocity on the order of a few cm/s. At the critical velocity for the onset of turbulence, the resonator velocity abruptly decreases and shows hysteretic behavior. Surprisingly we find that the resonant frequencies of the resonators increase in the turbulent regime. We also find that the critical velocity may be reduced by the presence of turbulence generated by a neighboring vibrating wire resonator, allowing the detection of existing turbulence in the low temperature regime.PACS numbers: 67.40 Vs, 67.40 Pm  相似文献   
10.
Chronic infection with Helicobacter pylori increases risk of gastric diseases including gastric cancer. Despite development of a robust immune response, H. pylori persists in the gastric niche. Progression of gastric inflammation to serious disease outcomes is associated with infection with H. pylori strains which encode the cag Type IV Secretion System (cag T4SS). The cag T4SS is responsible for translocating the oncogenic protein CagA into host cells and inducing pro-inflammatory and carcinogenic signaling cascades. Our previous work demonstrated that nutrient iron modulates the activity of the T4SS and biogenesis of T4SS pili. In response to H. pylori infection, the host produces a variety of antimicrobial molecules, including the iron-binding glycoprotein, lactoferrin. Our work shows that apo-lactoferrin exerts antimicrobial activity against H. pylori under iron-limited conditions, while holo-lactoferrin enhances bacterial growth. Culturing H. pylori in the presence of holo-lactoferrin prior to co-culture with gastric epithelial cells, results in repression of the cag T4SS activity. Concomitantly, a decrease in biogenesis of cag T4SS pili at the host-pathogen interface was observed under these culture conditions by high-resolution electron microscopy analyses. Taken together, these results indicate that acquisition of alternate sources of nutrient iron plays a role in regulating the pro-inflammatory activity of a bacterial secretion system and present novel therapeutic targets for the treatment of H. pylori-related disease.  相似文献   
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