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1.
Discusses a study by J. D. Laird (see record 1985-11387-001) that contrasted 16 successful demonstrations of the facial feedback hypothesis with R. Tourangeau and P. C. Ellsworth's (see record 1981-00499-001) failure to demonstrate any effects of facial expressions on mood. It is argued that Laird's conclusion that facial feedback effects have been demonstrated consistently and that the null results of the Tourangeau-Ellsworth study are atypical is more strongly worded than current evidence warrants. It is shown that most of the 16 successful studies are relevant only to the weak (dimensional) version of the hypothesis and not to the strong (categorical) version that Tourangeau and Ellsworth sought to test. (36 ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
2.
The author examined a public goods (PG) dilemma with environmental uncertainty in a sequential protocol of play paradigm. Using a 5-person game, Experiment 1 examined provision point (PP) uncertainty and found that a certain PP requiring 3 contributors produced the PG more frequently than an uncertain PP of the same expectation that varied uniformly among 2, 3, and 4 contributors. Fixing PP at 3, Experiment 2 showed that PG provision rate was higher with a certain group size of 5 persons than an uncertain group size of the same expectation that varied uniformly among 4, 5. and 6 persons. Further analyses showed that a fear of wasting one's contribution and pessimistic beliefs of environmental uncertainty could have undermined contribution. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Chemical kinetics parameters describing reactions of naturally-occurring clay minerals with acids were determined using batch reaction and analytical techniques. Clay minerals included sodium montmo-rillonite, kaolinite, and illite, reacting with hydrochloric acid, nitric acid, and sulfuric acid. Two acid concentrations were examined at 50 and 70°C. Displacement by acids of aluminum and magnesium from clays was found to follow pseudo-first order kinetics. Data analysis verified the batch reaction technique for determining kinetics parameters of acid-clay reactions and demonstrated acid neutralization by naturally-occurring clays. For reactions of sodium montmorillonite with hydrochloric acid, nitric acid, and sulfuric acid, reaction rate coefficients for displacement of aluminum ranged from 1·73 × 10-4 kg/mol-hr at 50°C to 3·02 × 10-3 kg/mol-hr at 70°C. Displacement of magnesium from sodium montmorillonite by these acids occurred at rates ranging from 3·68 × 10-4 kg/mol-hr at 50°C to 1·12 × 10-2 kg/mol-hr at 70°C. Activation energies for displacement by acids of aluminum from sodium montmorillonite were calculated to range from 31,000J/mol to 112,000J/mol, while activalion energies for displacement of magnesium from sodium montmorillonite ranged from 36.000 J/mol to 103,000 J/mol. For reactions of illite with acids, reaction rate coefficients for displacement of aluminum were determined to be 1·45×10-4Kg/mol-hr at 50°C to 1·7×10-3kg/mol-hr at 70°C. Displacement of magneisum by acids from illite occurred at rates from 6·06 × 10-4 kg/mol-hr at 50°C to 5·97 × 10-3 kg/mol-hr. Activation energies for reactions of acids with illite ranged from 33,000 J/mol to 62,000 J/mol for displacement of aluminum and from 9,400 J/mol to 29,000 J/mol for displacement of magnesium.  相似文献   
4.
Plane wave scattering is an important class of electromagnetic problems that is surprisingly difficult to model with the two-dimensional finite-difference time-domain (FDTD) method if the direction of propagation is not parallel to one of the grid axes. In particular, infinite plane wave interaction with dispersive half-spaces or layers must include careful modeling of the incident field. By using the plane wave solutions of Maxwell's equations to eliminate the transverse field dependence, a modified set of curl equations is derived which can model a "slice" of an oblique plane wave along grid axes. The resulting equations may be used as edge conditions on an FDTD grid. These edge conditions represent the only known way to accurately propagate plane wave pulses into a frequency dependent medium. An examination of grid dispersion between the plane wave and the modeled slice reveals good agreement. Application to arbitrary dispersive media is straightforward for the transverse magnetic (TM) case, but requires the use of an auxiliary equation for the transverse electric case, which increases complexity. In the latter case, a simplified approach, based on formulating the dual of the TM equations, is shown to be quite effective. The strength of the developed approach is illustrated with a comparison with the conventional simulation based on an analytic incident wave specification with half-space, single frequency reflection and transmission for the edges. Finally, an example of a possible biomedical application is given and the implementation of the method in the perfectly matched layer region is discussed.  相似文献   
5.
The hematologic abnormalities of SIV and HIV are well described, although the mechanisms that lead to hematopoietic dysfunction are yet to be fully defined. A number of growth factors and cytokines have been used to induce the differentiation, maturation, and proliferation of appropriate lineages, with the aim that such therapy will lead to functional hematopoietic reconstitution. Within this context, some cytokines have been shown to influence HIV and SIV replication in vitro and, in selected cases, in vivo. However, few studies detail the effects of hematopoietic cytokines such as IL-3, Flt-3 ligand, G-CSF, Tpo, and Epo or correlate the effects on virus replication. In an effort to address this issue, we infected 12 rhesus macaques with 500 TCID50 of SIVmac239 and intensively evaluated hematologic, virologic, and immunologic parameters during administration of cytokines. When all animals had lymphadenopathy, hepatosplenomegaly, and CD4+ cell counts > or =1000/microl, subgroups of three rhesus macaques were administered either rhFlt-3; rrIL-3a; combination of rhG-CSF, rhTpo, and rhEpo (rhGET); or rrIL-12. Fourteen days of rhFlt-3 administration induced expansion of the bone marrow CD34+ cells and granulocyte-macrophage colony-forming units (GM-CFUs) and increased absolute peripheral blood CD34+ cells and total CFUs. Following rrIL-3 and rhGET administration absolute peripheral blood CD34+ cells and total CFUs increased. rhGET also increased granulocyte, platelet, and reticulocyte counts by day 14 of administration. Branched DNA and coculture assays did not demonstrate any significant change in viral load with any of the cytokines administered. These data suggest that SIV-infected rhesus macaques have the hematopoietic capability to expand and mobilize CD34+ and GM-CFU progenitors and formed elements at 6-8 months postinfection in response to various cytokines, without increasing viral load.  相似文献   
6.
7.
Many applications that work well in a development environment may fail in a live operational environment because they can not be monitored and managed. The potential problems in a distributed client/server environment are even greater. This paper describes some of the main issues and the environment within BT into which new applications must fit. It then discusses the innovative work done to address the problems of providing a comprehensive and extensible solution for BTs Distributed Computing Environment-based applications.  相似文献   
8.
A coal burst is defined as a rapid expulsion of coal(and potentially gas) from the boundary of the roadway. Rock and coal fractures together with micro seismic vibration is a common occurrence during mining, however, it is very uncommon for coal and rock to be propelled into the roadway. Irrespective, such occurrences do occur and appear to require significantly more energy than is available from strain energy release during coal cutting. The sources of energy which can contribute to the propulsion of coal from the face or ribs are typically strain energy from the surrounding ground, seismic energy from a rapid rupture of the ground in the vicinity, or rapid expansion of gas from within the burst source area. The aim of this paper is to briefly review the bursts which may be related to strain energy, seismic energy and gas energy.  相似文献   
9.
OBJECTIVE: To determine the effects of controlled ovarian hyperstimulation (COH) on endometrial maturation. DESIGN: Prospective, before and after evaluation of midluteal endometrial biopsies in oocyte donor's spontaneous and subsequent COH cycles. SETTING: Tertiary academic medical center assisted reproductive technologies clinic. PATIENT(S): Nineteen oocyte donors. INTERVENTION(S): Exogenous gonadotropins, endometrial biopsies. MAIN OUTCOME MEASURE(S): Endometrial histology and an immunohistochemical marker of uterine receptivity, the alphavbeta3 vitronectin. RESULT(S): Glandular and stromal dyssynchrony was more common after COH in 16 (80%) of 20 cycles than 6 (30%) of 20 spontaneous cycles (P <.05). Glandular lag was more frequent in COH cycles and unaffected by progesterone administration. The beta3 subunit of the alphavbeta3 vitronectin receptor was present in 9 (45%) of 20 spontaneous and 2 (10%) of 20 COH cycles (P <.05). CONCLUSION(S): Exogenous gonadotropin use in healthy reproductive age women did not result in endometrial evidence of a luteal phase defect. A greater incidence of glandular-stromal dyssynchrony resulted from the use of exogenous gonadotropins. The presence of alphavbeta3 was noted in most endometrial specimens demonstrating in phase glandular maturation. We conclude that endometrial dyssynchrony that results from delayed glandular development most likely represents a normal histologic variant.  相似文献   
10.
Argues that to the extent that the work of R. M. Yerkes and J. D. Dodson (1908; Yerkes, 1909) is identified with the concept of general arousal or activation, their findings are presented anachronistically—the arousal construct was not developed until several decades after their research was published. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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