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1.
Reading Motivation: Multidimensional and Indeterminate. 总被引:1,自引:0,他引:1
The Motivations for Reading Questionnaire (MRQ) contains 54 items that are posited to tap 11 dimensions of reading motivation. The structural validity of the MRQ was investigated with 2 samples: (a) 328 students in Grades 3-5 from 2 suburban mid-Atlantic elementary schools and (b) 735 students in Grades 3-5 in 2 suburban southwestern elementary schools. With confirmatory factor analyses (CFAs), the theoretical 11-factor structure did not adequately fit the data in either sample. Subsequently, exploratory factor analyses found 8 factors for each sample with 6 factors defined by only 3 or 4 common items. However, a double CFA cross-validation found an inadequate fit for both samples. Given these results, the authors suggest that the MRQ be revised. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Heritabilities were estimated for lactation average log, base 2, somatic cell count from cows with four or more tests in each lactation. Estimates were for first, second, and third or later parities (defined by age at calving) individually and for mixed parities. Estimates were from sire components of variance with numbers of sires and daughters of 406 and 22,140; 337 and 8,659; 311 and 6,122; and 310 and 10,217 for mixed, first, second, and third or later parities, respectively.Both sire and error components of variance increased with parity. Heritabilities were .18, .09, .10, and .29, for mixed, first, second, and third or later parities. 相似文献
4.
The technique of continuous-flow solid-phase peptide synthesis using unsupported polymers has been extended to cover the use of N alpha-Fmoc protected amino acids. This approach to peptide synthesis uses (but is not limited to) a phenolic bead-form polymer at 5 mmol g-1 loading. The success of the technique is based upon "layered displacement" to efficiently remove spent reagents and washing solutions from within the flow reactor under low pressure conditions. This system has been successfully employed in synthesizing the test peptides, [Leu5]-enkephalin, neurotensin and the notoriously difficult decapeptide sequence (65-74) of the acyl carrier protein. 相似文献
5.
S. McParland G. Banos B. McCarthy E. Lewis M.P. Coffey B. O’Neill M. O’Donovan E. Wall D.P. Berry 《Journal of dairy science》2012
Cow energy balance is known to be associated with cow health and fertility; therefore, routine access to data on energy balance can be useful in both management and breeding decisions to improve cow performance. The objective of this study was to determine if individual cow milk mid-infrared spectra (MIR) could be useful to predict cow energy balance across contrasting production systems. Direct energy balance was calculated as the differential between energy intake and energy output in milk and maintenance (maintenance was predicted using body weight). Body energy content was calculated from (change in) body weight and body condition score. Following editing, 2,992 morning, 2,742 midday, and 2,989 evening milk MIR records from 564 lactations on 337 Scottish cows, managed in a confinement system on 1 of 2 diets, were available. An additional 844 morning and 820 evening milk spectral records from 338 lactations on 244 Irish cows offered a predominantly grazed grass diet were also available. Equations were developed to predict body energy status using the milk spectral data and milk yield as predictor variables. Several different approaches were used to test the robustness of the equations calibrated in one data set and validated in another. The analyses clearly showed that the variation in the validation data set must be represented in the calibration data set. The accuracy (i.e., square root of the coefficient of multiple determinations) of predicting, from MIR, direct energy balance, body energy content, and energy intake was 0.47 to 0.69, 0.51 to 0.56, and 0.76 to 0.80, respectively. This highlights the ability of milk MIR to predict body energy balance, energy content, and energy intake with reasonable accuracy. Very high accuracy, however, was not expected, given the likely random errors in the calculation of these energy status traits using field data. 相似文献
6.
Using the four input-output tables compiled in Turkey to date, the aim of this paper is to examine the construction sector's role in the Turkish economy and analyse its relationships with the other sectors of the national economy. Analysis results show that the share of construction in Gross National Product (GNP) and National Income (NI) tend to increase whereas the GNP share of manufacturing is relatively stable and that of services tend to increase after an abrupt decrease in 1985; backward linkage indicators and output multipliers, as well as forward linkage indicators and input multipliers of construction industry are stable; and finally, direct and total construction inputs from manufacturing show relative stability and those from services tend to increase in recent years. These findings point out the similarities between the Turkish construction industry and some advanced industrial countries (AICs) like Japan and Italy showing signs of growing ‘maturity’ of the Turkish economy. 相似文献
7.
DE Epner AW Partin JA Schalken JT Isaacs DS Coffey 《Canadian Metallurgical Quarterly》1993,53(9):1995-1997
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression is increased in Dunning R-3327 rat prostatic adenocarcinoma cell lines relative to normal rat ventral prostate tissue. GAPDH expression closely correlates with cell motility of Dunning prostate cancer cell lines and accurately distinguishes cell lines with high metastatic potential from those with low metastatic potential. Increased GAPDH expression in the cancer cell lines is not simply related to increased growth rate, since rapidly proliferating normal prostate tissue did not exhibit elevated GAPDH expression. 相似文献
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9.
Fare TL Coffey EM Dai H He YD Kessler DA Kilian KA Koch JE LeProust E Marton MJ Meyer MR Stoughton RB Tokiwa GY Wang Y 《Analytical chemistry》2003,75(17):4672-4675
A data anomaly was observed that affected the uniformity and reproducibility of fluorescent signal across DNA microarrays. Results from experimental sets designed to identify potential causes (from microarray production to array scanning) indicated that the anomaly was linked to a batch process; further work allowed us to localize the effect to the posthybridization array stringency washes. Ozone levels were monitored and highly correlated with the batch effect. Controlled exposures of microarrays to ozone confirmed this factor as the root cause, and we present data that show susceptibility of a class of cyanine dyes (e.g., Cy5, Alexa 647) to ozone levels as low as 5-10 ppb for periods as short as 10-30 s. Other cyanine dyes (e.g., Cy3, Alexa 555) were not significantly affected until higher ozone levels (> 100 ppb). To address this environmental effect, laboratory ozone levels should be kept below 2 ppb (e.g., with filters in HVAC) to achieve high quality microarray data. 相似文献
10.
A method of test is described for the determination of dry shortening air content. Liquid mediums are prepared which have
identical specific gravity to that of the shortening which is under test. Simple calculation of specific gravity data gives
the air content. A distinct advantage to the method lies in the fact that air content can be determined for any shortening
sample size. 相似文献