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排序方式: 共有964条查询结果,搜索用时 15 毫秒
61.
Previous research has demonstrated the superiority of a Simultaneous Oral Spelling method for young children beginning to learn to spell words. In this technique, children learn words by repeating a word spoken and written for them, writing the word while pronouncing the name of each letter, and then repeating the whole word again. In two experiments, we manipulated the motoric element of this training and obtained results indicating that having first-grade children write words leads to better spelling performance than having the children type them on a computer or manipulate letter tiles to spell them. The superiority of handwriting was maintained even under conditions where post-training spelling assessment was done on the computer and with tiles. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Cunningham Michael R.; Barbee Anita P.; Pike Carolyn L. 《Canadian Metallurgical Quarterly》1990,59(1):61
The multiple motive hypothesis of physical attractiveness suggests that women are attracted to men whose appearances elicit their nurturant feelings, who appear to possess sexual maturity and dominance characteristics, who seem sociable, approachable, and of high social status. Those multiple motives may cause people to be attracted to individuals who display an optimal combination of neotenous, mature, and expressive facial features, plus desirable grooming attributes. Three quasi-experiments demonstrated that men who possessed the neotenous features of large eyes, the mature features of prominent cheekbones and a large chin, the expressive feature of a big smile, and high-status clothing were seen as more attractive than other men. Further supporting the multiple motive hypothesis, the 2nd and 3rd studies indicated that impressions of attractiveness had strong relations with selections of men to date and to marry but had a curvilinear relation with perceptions of a baby face vs a mature face. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Howard John H.; Cunningham David A.; Rechnitzer Peter A. 《Canadian Metallurgical Quarterly》1986,71(1):95
Studied 217 male managers (mean age 44 yrs), classified as Type A (coronary-prone) or Type B (non-coronary-prone), to examine the effects of job satisfaction as a moderator between a common job stressor (role ambiguity) and coronary risk indicators. For Type A's, the results support the hypotheses that changes in ambiguity are associated with changes in blood pressure and that intrinsic job satisfaction has both a direct and moderating effect on these changes. Few similar effects were found for extrinsic job satisfaction. For Type B's, the effects on systolic blood pressure were opposite to those for type A's. It is suggested that either Type A's and Type B's differ in autonomic and cardiovascular response or that ambiguity as a stressor may have differential effects for Type A's and Type B's, indicating that their "fit" with ambiguous environments may be opposite. (53 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Chaffee C. Anne; Cunningham Charles E.; Secord-Gilbert Margaret; Elbard Heather; Richards Joanne 《Canadian Metallurgical Quarterly》1990,2(1):80
This study examines the sensitivity, specificity, and predictive value of the Expressive Language (EL) and Comprehension-Conceptual (CC) subscales of the Minnesota Child Development Inventory (MCDI) in 152 consecutive referrals to a communication disorders clinic. Correlational analyses revealed moderate agreement between parent report (MCDI) and formal measures of expressive and receptive language ability from the Reynell Development Language Scales. Classification analyses comparing parent-report (MCDI) measures with direct assessment results (Reynell) revealed high sensitivity (88% and 77%) and good positive predictive value (80% and 75%) for the MCDI EL and CC subscales, respectively. Low to moderate specificity rates, however, suggest that the MCDI classifies normal expressive and receptive language status less accurately (45% and 64%, respectively). These findings suggest that the MCDI is an efficient screening tool under high-prevalence conditions such as a clinic population of language-disordered children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
CL Zani E Chiari AU Krettli SM Murta ML Cunningham AH Fairlamb AJ Romanha 《Canadian Metallurgical Quarterly》1997,5(12):2185-2192
Naphtho[2,3-b]thiophen-4,9-quinone and five derivatives were prepared using the Friedel-Crafts reaction and tandem-lithiation of aromatic diethylamides. These quinones were evaluated for their trypanocidal and anti-plasmodial activities by their effects on: (1) growth of epimastigote forms of Trypanosoma cruzi in vitro, (2) lysis of trypomastigote forms of T. cruzi in murine blood, (3) growth of Plasmodium falciparum in vitro, and (4) inhibition of the recombinant enzyme trypanothione reducatase. The parent compound, naphtho[2,3-b]thiophen-4,9-quinone (3a), was among the most active quinone tested in vitro against P. falciparum at 0.2 microM. However, it was inactive against P. berghei-infected mice treated with 2.3 mmol/kg daily for 5 days. Most of the quinones prepared were active against T. cruzi epimastigotes in culture but exhibited weak activity at 4 degrees C against trypomastigotes in murine blood as well against the enzyme trypanothione reducatase. Further structural modifications will be necessary to improve the in vivo activity of the naphthothiophenquinones. 相似文献
66.
67.
Eoin Cunningham Nicholas Dunne Gavin Walker Christine Maggs Ruth Wilcox Fraser Buchanan 《Journal of materials science. Materials in medicine》2010,21(8):2255-2261
The application of synthetic cancellous bone has been shown to be highly successful when its architecture mimics that of the
naturally interconnected trabeculae bone it aims to replace. The following investigation demonstrates the potential use of
marine sponges as precursors in the production of ceramic based tissue engineered bone scaffolds. Three species of natural
sponge, Dalmata Fina (Spongia officinalis Linnaeus, Adriatic Sea), Fina Silk (Spongia zimocca, Mediterranean) and Elephant Ear (Spongia agaricina, Caribbean) were selected for replication. A high solid content (80 %wt), low viscosity (126 mPas) hydroxyapatite slurry
was developed, infiltrated into each sponge species and subsequently sintered, producing a scaffold structure that replicated
pore architecture and interconnectivity of the precursor sponge. The most promising of the ceramic tissue engineered bone
scaffolds developed, Spongia agaricina replicas, demonstrated an overall porosity of 56–61% with 83% of the pores ranging between 100 and 500 μm (average pore size
349 μm) and an interconnectivity of 99.92%. 相似文献
68.
A dilute mixture of CCl4 in H2 has recently been shown to be a suitable carbon doping source for obtainingp-type GaAs grown by metalorganic chemical vapor deposition (MOCVD) with carbon acceptor concentrations in excess of 1 × 1019cm−3. To understand the effect of growth parameters on carbon incorporation in CCl4 doped Al
x
Ga1−x
As, carbon acceptor concentration was studied as a function of Al composition, growth temperature, growth rate, and CCl4 flow rate using electrochemical capacitance-voltage profiling. The carbon incorporation as a function of Al composition,
growth temperature and CCl4 flow rate was also measured by secondary ion mass spectroscopy (SIMS). All layers were grown by low pressure MOCVD using
TMGa and TMAl as column III precursors, and 100% AsH3 as the column V source. Increased Al composition reduced the dependence of carbon concentration on the growth temperature.
Reduced growth rate, which resulted in substantially decreased carbon acceptor concentrations in GaAs, had an insignificant
effect on the carrier concentration of Al0.4Ga0.6As. A linear relationship between hole concentration and CC14 flow rate in AlxGa1−x
As for 0.0 ≤x ≤ 0.8 was observed. These results are interpreted to indicate that adsorption and desorption of CCl
y
(y ≤ 3) on the Al
x
Ga1-x
As surface during crystal growth plays an important role in the carbon incorporation mechanism. 相似文献
69.
Yeast KEX2 protease and mannosyltransferase I are localized to distinct compartments of the secretory pathway 总被引:25,自引:0,他引:25
The KEX2 protease (product of the KEX2 gene) functions late in the secretory pathway of Saccharomyces cerevisiae by cleaving the polypeptide chains of prepro-killer toxin and prepro-alpha-factor at paired basic amino acid residues. The intracellular vesicles containing KEX2 protease sedimented in density gradients to a position distinct from those containing mannosyltransferase I (product of the MNN1 gene), a marker enzyme for the Golgi complex. The recovery of intact compartments containing these enzymes approached 80% after sedimentation. We propose that the KEX2 protease and mannosyltransferase I reside within distinct compartments. 相似文献
70.
A computationally efficient method of determining the temperature distribution and stress intensity factor induced by the resistance heating method of cycling temperature in thermo-mechanical fatigue is presented. It is further used to evaluate the importance of the singularity of the heat source caused by the electric current. Results indicate the thermally induced stress intensity factor of cracked components cycled by the direct resistance method of heating increases with the frequency of the thermal loading and may become quite large at higher frequencies. 相似文献