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81.
ABSTRACT: The usual Third World pattern of urbanization does not apply to Chinese urban development. China has not experienced the overurbanization and imbalances that often accompany growth in cities elsewhere. China's unique urban pattern results from national policies aimed at shaping urban growth. When those policies were relaxed, there was a tendency for Chinese urban patterns to conform with those of other Third World nations. Periods of less control corresponded with periods of experimentation with elements of a market economy and China's entry in the world economy. The authors explore the debate between urban bias theory and world system theory by considering how global structures and processes interact with local or national policies. 相似文献
82.
GLADYS BOISON MICHAEL V. TARANTO MUNIR CHERYAN 《International Journal of Food Science & Technology》1983,18(6):719-730
Defatted soy flour containing low levels of added hydrocolloid (either sodium alginate or methylcellulose) was thermoextruded in a laboratory single-screw extruder, and the effect of operating parameters on selected textural properties (maximum peak force, determined in an Ottawa Measuring (OTMS) cell, and chewiness) and physical properties (bulk density and water absorption capacity) were studied. Adding sodium alginate generally increased OTMS peak force, chewiness and water absorption capacity and increased bulk density. Extruding at a feed moisture content of 22% w/w resulted in the best properties, regardless of the levels of other independent variables. Maximum force and chewiness were positively correlated while bulk density and water absorption capacity were negatively correlated to each other. 相似文献
83.
84.
ANDREW G. F. STAPLEY JOSÉ A. SOUSA GONÇALVES MICHAEL P. HOLLEWAND LYNN F. GLADDEN PETER J. FRYER 《International Journal of Food Science & Technology》1995,30(5):639-654
Experiments have been carried out using pulsed field gradient NMR to characterize the self-diffusion of water within samples of carrot, both uncooked and cooked by either volumetric electrical or conventional heating. The method detected the presence of structure within uncooked carrot, and the disappearance of the structure on cooking. The NMR data were fitted to two models: (i) an analytical solution for diffusion between impermeable barriers and (ii) a numerical solution to the more physically realistic situation of diffusion between permeable barriers. The barrier spacings obtained with raw carrot data using both methods (i) and (ii) were consistent with cell sizes found in carrots. The effect of cooking on the model fit was either an increase in barrier spacing (method i), or an increase in barrier permeability (method ii). There was a statistically significant difference between samples cooked electrically and conventionally, but this was much less than the difference between cooked and uncooked material. 相似文献
85.
IDENTIFICATION OF THE MAJOR VOLATILE COMPONENTS OF BLUEBERRY 总被引:3,自引:0,他引:3
86.
BOVINE MUSCLE TENDERNESS AS RELATED TO PROTEIN SOLUBILITY 总被引:1,自引:0,他引:1
ABSTRACT— The longissimus (modest degree of marbling) from forty beef ribs selected 48–56 hr post-mortem was used in two trials. Trial I involved A, C and E maturity ribs (10 each classification). Each rib was subjectively scored for texture (fresh) and adjacent longissimus samples were removed for the determination of protein solubility (fresh) and tenderness. Tenderness (cooked muscle) was measured with a Warner-Bratzler shear and taste panel. Protein solubilities were determined using 0.154M Krebs-Ringer-Bicarbonate buffer, 0.2M KCl + 0.01M K phosphate buffer, 1.1M Kl + 0.1M K phosphate buffer, and 0.03M K phosphate buffer. Trial II involved 10 A maturity ribs. The 0.2M KCl, 1.1M Kl and 0.03M K phosphate buffers as described for trial I were used for protein extraction. Additionally, sarcomere length was measured in formalin. Multiple regression equations were developed to predict tenderness in trial II. Protein solubilities were not significantly different between the carcass maturity groups although there were trends toward increased solubility as maturity increased. Tenderness tended to decrease from A to E maturity indicating a negative relationship between protein solubility and tenderness. Several significant negative correlations between protein solubility and tenderness were found in trial I (A maturity group) and trial II. Additionally, several significant negative correlations between texture and solubility were calculated. Correlations within the C and E maturity groups were variable and showed no definite trends. Multiple regression analyses showed that a combination of protein solubilities, texture score and sarcomere length accounted for 88% of the variation in shear force and 72% of the variation in taste panel tenderness. 相似文献
87.
BIOELECTRIC RECORDINGS AND VERBAL REPORTS OF MENTAL ACTIVITIES WERE COLLECTED FROM 10 SS DURING 6 HR. OF SENSORY DEPRIVATION. SS AND 3 EXPERTS INDEPENDENTLY RATED THE REPORTS FOR TYPE OF THOUGHT PROCESS, LEVEL OF THOUGHT ORGANIZATION, AND THEIR LEVEL OF AROUSAL DURING THE REPORT PERIOD. RESULTS INDICATE THAT SS ARE NOT HIGHLY ACCURATE RATERS FOR THE 3 CATEGORIES MENTIONED, AND THE MAJORITY OF THOUGHT DISORGANIZATIONS AND NONREALITY-ORIENTED THOUGHT PROCESSES OCCUR DURING LOW LEVELS OF AROUSAL. THE CONCLUSION REACHED IS THAT SENSORY DEPRIVATION DOES NOT DISRUPT THE NORMAL RELATIONSHIP BETWEEN LEVELS OF AROUSAL AND THOUGHT PROCESSES, BUT IN THE ABSENCE OF USUAL ENVIRONMENTAL CUES SS MAY MISINTERPRET THEIR MENTAL EXPERIENCES. (22 REF.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
MICHAEL C. WEINBERG R. SHANKAR SUBRAMANIAN 《Journal of the American Ceramic Society》1980,63(9-10):527-531
The behavior of an isolated, stationary, multicomponent gas bubble in a glassmelt containing several dissolved gases is considered. The relevant mass-transport equations are formulated and calculations are performed for the case of two diffusing gases using a quasi-stationary model and a numerical solution of the exact mass-transfer equations. The results obtained from these two approaches are compared. The factors which govern the dissolution or growth of a bubble are thermodynamic and kinetic in origin. The tendency of a bubble to grow or shrink at long times is controlled by departure from overall equilibrium, whereas the short-time bubble dynamics may be dominated by kinetic effects. As a result of the existence of these dual influences, maxima and/or minima occur in the functional dependence of the bubble radius on time. 相似文献
89.
A method has been developed for the determination of the thermal conductivities of anisotropic solids under conditions of two–dimensional, steady–state heat conduction in a cylinder of finite length heated in vacuum by high–frequency induction and radiating heat to the surroundings. The method has been used to determine the radial thermal conductivity, Kr , and the axial thermal conductivity, Kz , of molded ZT-type and pyrolytic graphite in the temperature range 1260° to 2200°K. For ZT-type graphite, Kz /Kr =–0.101 + 2.002 × 10−4 ± T (1260°K < T < 2200°K); for pyrolytic graphite, Kz /Kr = 0.0376 at 1817°K. 相似文献
90.
MICHAEL C. WEINBERG PAULETTE I. K. ONORATO DONALD R. UHLMANN 《Journal of the American Ceramic Society》1980,63(3-4):175-180
The quasi-stationary approximation was used to calculate the rates of dissolution of O2 and CO2 gas bubbles from a soda-lime glassmelt. An analytic expression for the bubble radius as a function of time, R(t) , was obtained when surface tension was neglected and numerical results for R(t) were found when surface-tension effects were included. These results were compared with those found by previous investigators. Also, an asymptotic expression for R (t) was derived and used to calculate bubble dissolution times. 相似文献