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41.
P. N. Tandon P. Nirmala M. Tewari U. S. Rana 《Computers & Mathematics with Applications》1991,22(12):3-13
Presented herein are the studies of nutritional transport from capillary to tissues in normal and stenosed arteries. The model incorporates modified Casson's fluid representation for the blood and symmetric stenosis has been assumed at some distance from the entry. Assessment of the severity of the disease could be made possible through the variation of a parameter named as retention parameter. Nutritional flux at the capillary wall is affected by the growing stenosis and its variation has been observed through a decreasing trend of the retention parameter from 1 to 0. Results for local variation of viscosity contrary to Fahraeus-Lindquist effect have been explained. Symmetry of the distribution of the wall shearing stress and resistance to flow and their growth with the developing stenosis is another important feature of this analysis. Taylor diffusivity coefficient increases considerably with growing stenosis and the nutritional transport to the deeper cells of the tissue will naturally decrease. 相似文献
42.
S. N. Tewari) 《Metallurgical and Materials Transactions A》1988,19(7):1711-1720
Chill block melt spun ribbons of nickel molybdenum alloys with molybdenum contents of 8 to 41.8 wt pct Mo have been examined
for their microstructure and texture dependence on processing conditions. Linear features observed in grains solidified with
a planar liquid-solid interface at the quench side of the ribbons have been identified to be due to the twins on (111),, plane
formed during solidification. Grain size variation with the wheel surface speed and the alloy composition has been studied.
Crystallographic texture on quench side and free surface side of the ribbons has been investigated. 相似文献
43.
44.
H. K. Tewari S. S. Marwaha J. F. Kennedy L. Singh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1988,41(4):261-275
This paper reports the results of experimentation carried out to compare the ability of mineral acids (HCl and H2SO4) and cellulase enzyme (from Trichoderma reesei QM 9414) in the saccharification of corn-cob, groundnut shell, sugarcane bagasse and wheat straw. With the exception of corn-cobs, acids proved to be better saccharifying agents than the cellulase complex, but the former gave a poor substrate for alcoholic fermentation since the saccharified mashes contained large amounts of pentoses which are not metabolized by most strains of yeast. In addition, both acids and enzymes have been found to be substrate specific. Maximal saccharification of groundnut shell, sugarcane bagasse and wheat straw were obtained with sulphuric acid at 15.0, 5.0 and 5.0% (v/v) under 15, 15 and 15 psi pressure for 15, 30 and 30 min, respectively; whereas hydrochloric acid at 7.5% (v/v) with. autoclaving for 30 min at 10 psi resulted in maximum saccharification of corn-cob. However, the order of susceptibility of substrates to enzymatic attack was corn-cob > wheat straw > sugarcane bagasse > groundnut shell. Increase in enzyme concentration (1–4 IU ml?1) and treatment duration (12–72 h) improved saccharification, but increases in substrate concentration (>5.0%, w/v) had an inhibitory effect on the hydrolytic ability of the cellulase enzyme complex. Of the various substrate-acid ratios tested, a ratio of 1:8 was found to be optimal for the eflcient hydrolysis of the substrates under study. 相似文献
45.
This paper describes some basic considerations in the design and development of a horizontal axis windmill intended primarily
for irrigation in small farms from shallow open wells. This windmill has six triangular sails sweeping a circle of 10 m diameter
and is an adaptation from Greek sail windmills. For the construction of this windmill all efforts were made to use materials
and parts readily available in the hardware market except for the gear boxes. The cost of material and the parts is Rs. 7,000/-
excluding the cost of machining and fabrication. Preliminary performance tests have indicated a pumping rate of 6000–11000
litres/hr over a head of 6.85 m in wind speeds of 10–16 km/hr. 相似文献
46.
The administration of calcitonin (4 MRC units injected intraperitoneally daily for 42 days) caused hypocalcaemia, hypophosphataemia and a decrease in the serum acid phosphatase level in adult Indian palm squirrels, Funambulus pennanti. Hypocalcaemia and the decrease in the serum acid phosphatase level persisted up to 21 days but the hypophosphataemic effect continued throughout the experiment. The serum calcium level increased from day 28 up to day 35 and the serum acid phosphatase level reached the control level at 28 days. At the close of the experiment (42 days), both serum calcium and acid phosphatase levels were again decreased. Calcitonin-induced hypocalcaemia resulted in hypertrophy of calcitonin cells which were densely packed with secretory granules up to day 21 of the treatment. Thereafter they displayed both hypertrophy and hyperplasia till the end of the experiment. Some calcitonin cells showed degranulation after 35 and 42 days of treatment. Few lead-haematoxylin-positive calcitonin cells with collapsed membranes and pyknotic nuclei were also seen in the lumina of the thyroid follicles toweards the close of the experiment. Parathyroid chief cells showed hypertrophy from 21 to 35 days of the treatment. From day 28 to the close of the experiment they released their secretory product. After 42 days of experimental treatment a growth-promoting effect of calcitonin was observed (increase in body weight and femur weight. 相似文献
47.
In this paper a method to determine the appropriateness of energy resources in rural applications is discussed. Feasible energy
resources are comparatively evaluated using eight attributes representing the criteria of appropriateness. ‘Appropriateness’
is defined as a linear combination of attribute weights multiplied by attribute attainment levels which have been mapped into
utility for decision-makers. The uncertainty in data is handled using Monte-Carlo techniques. Sample results indicate a set
of dominant energy resources for a particular task. This method can be applied in real-life decision making concerning energy
resources for rural applications. 相似文献
48.
Upgraded coal-derived liquids obtained from catalytic hydroprocessing of a 30–70(wt%) blend of SRC-1 with SRC-II have been studied by infrared and proton magnetic resonance spectroscopy, and gel permeation chromatography techniques. Compared with the feed blend, the upgraded liquids exhibit a lower C/H ratio and decreased aromatic, heteroatom and pentane-insoluble contents, along with decreased specific gravity and viscosity. The amount of hydrogen-bonded structure in the upgraded liquid decreases with increases in residence time and processing temperature. The pseudo-first-order disappearance of phenolic OH and total nitrogen during processing indicates a relative reactivity of 2:1 of hydroxyl oxygen removal to total nitrogen removal in the upgrading process. Conversion of pentaneinsolubles to soluble oil also follows a pseudo-first-order reaction; under mild processing conditions, the heteroatom functionalities play a dominant role in the ease and extent of this conversion. Higher temperatures increase thermal cracking and hydrocracking of the ring structure resulting in more conversion of asphaltene to oil. The linear dependence of the logarithm of viscosity on the content of heteroatoms and toluene-insolubles (TI) indicates the importance of molecular interactions involving polar functional groups in defining the viscosity of coal-derived liquid. 相似文献
49.
50.
Kathiravan Krishnamurthy Jagdish C. Tewari Joseph Irudayaraj Ali Demirci 《Food and Bioprocess Technology》2010,3(1):93-104
Pulsed UV light and infrared heat-treated Staphylococcus aureus cells were analyzed using transmission electron microscopy to identify the cell damage due to the treatment process. A 5-s
treatment with pulsed UV light resulted in complete inactivation of S. aureus even after enrichment. The temperature increase during the pulsed UV light treatment was insignificant, which suggested a
nonthermal treatment. S. aureus was also infrared heat treated using an infrared heating system with six infrared lamps. Five milliliters of S. aureus cells in phosphate buffer was treated at 700°C lamp temperature for 20 min. The microscopic observation clearly indicated
that there was cell wall damage, cytoplasmic membrane shrinkage, cellular content leakage, and mesosome disintegration after
both pulsed UV light and infrared treatments. Fourier transform infrared microspectrometry was successfully used to classify
the pulsed UV light and infrared heat-treated S. aureus by discriminant analysis. 相似文献