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61.
The ability of five strains of different bifidobacterial species (Bifidobacterium animalis, B. bifidum, B. infantis, B. longum, B. pseudolongum) isolated from human and animal gut to degrade myo-inositol hexaphosphate or phytic acid (InsP(6)) has been evaluated. The disappearance of phytate and the generation of lower myo-inositol phosphates were determined in a complex medium in which phytic acid was the only source of phosphorus. Bifidobacterium infantis ATCC 15697 showed the highest level of phytate-degrading activity. This strain displayed optimal activity at slight acid pH (6.0-6.5) and 50 degrees C, but also retained high activity levels at neutral pH and 37 degrees C. B. infantis ATCC 15697 produced maximum activity during the stationary phase of growth and when 1% lactose was used as carbon source. In contrast, the presence of inorganic phosphate in the growth medium inhibited phytase activity. The ability of B. infantis ATCC 15697 to generate lower myo-inositol phosphates and, particularly, accumulate myo-inositol tri-phosphates (InsP(3)) from partial hydrolysis of InsP(6) could contribute to the reduction of the anti-nutritional properties of InsP(6) and the generation of intermediate compounds with beneficial properties during food processing and gastrointestinal transit. 相似文献
62.
Andro Mondala Rafael Hernandez William Holmes Todd French Linda McFarland Darrell Sparks Monica Haque 《American Institute of Chemical Engineers》2013,59(11):4036-4044
The co‐fermentation of glucose and xylose by activated sludge microorganisms for the production of microbial oils for use as biodiesel feedstock was investigated. Various carbon sources at initial concentration of 60 g/L and C:N ratio 70:1 were investigated: xylose, glucose, and 2:1 and 1:2 (by mass) glucose/xylose mixtures. Oil accumulation ranged between 12 to 22% CDW, the highest of which was obtained when xylose was the sole substrate used. Kinetic modeling of the fermentation data showed that specific growth and oil accumulation rates were similar in all substrate types and the lipid coefficient ranged from 0.02 to 0.06 g/g of sugar consumed. The fatty acid methyl ester yield and composition of the lipids showed their suitability for conversion to biodiesel. Based on the results, lignocellulose sugars could be used as fermentation substrates by activated sludge microorganisms for enhancing the oil content of sewage sludge for its use as a sustainable biofuel feedstock source. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4036–4044, 2013 相似文献
63.
The Falling Lake Victoria Water Level: GRACE,TRIMM and CHAMP Satellite Analysis of the Lake Basin 总被引:2,自引:0,他引:2
Joseph L. Awange Mohammad A. Sharifi Godfrey Ogonda Jens Wickert Erik W. Grafarend Monica A. Omulo 《Water Resources Management》2008,22(7):775-796
In the last 5 years, Lake Victoria water level has seen a dramatic fall that has caused alarm to water resource managers.
Since the lake basin contributes about 20% of the lakes water in form of discharge, with 80% coming from direct rainfall,
this study undertook a satellite analysis of the entire lake basin in an attempt to establish the cause of the decline. Gravity
Recovery And Climate Experiment (GRACE), Tropical Rainfall Measuring Mission (TRMM) and CHAllenging Minisatellite Payload
(CHAMP) satellites were employed in the analysis. Using 45 months of data spanning a period of 4 years (2002–2006), GRACE
satellite data are used to analyse the variation of the geoid (equipotential surface approximating the mean sea level) triggered
by variation in the stored waters within the lake basin. TRMM Level 3 monthly data for the same period of time are used to
compute mean rainfall for a spatial coverage of .25°×.25° (25×25 km) and the rainfall trend over the same period analyzed.
To assess the effect of evaporation, 59 CHAMP satellite’s occultation for the period 2001 to 2006 are analyzed for tropopause
warming. GRACE results indicate an annual fall in the geoid by 1.574 mm/year during the study period 2002–2006. This fall
clearly demonstrates the basin losing water over these period. TRMM results on the other hand indicate the rainfall over the
basin (and directly over the lake) to have been stable during this period. The CHAMP satellite results indicate the tropopause
temperature to have fallen in 2002 by about 3.9 K and increased by 2.2 K in 2003 and remained above the 189.5 K value of 2002.
The tropopause heights have shown a steady increase from a height of 16.72 m in 2001 and has remained above this value reaching
a maximum of 17.59 km in 2005, an increase in height by 0.87 m. Though the basin discharge contributes only 20%, its decline
has contributed to the fall in the lake waters. Since rainfall over the period remained stable, and temperatures did not increase
drastically to cause massive evaporation, the remaining major contributor is the discharge from the expanded Owen Falls dam. 相似文献
64.
Nader Tehrani Dan Gallagher Monica Ponce de Leon Harry Lowd Richard Lee Lisa Huang Remon Alberts Janghwan Cheon Jumanah Jamal Aishah Al Sager 《世界建筑导报》2018,(2)
正Banq餐厅位是一家新型餐厅,位于便士储蓄银行(Penny Savings Bank)旧大楼以前用来经营银行业务的大厅内。餐厅分成两个部分,前面区域面向华盛顿大街,设计成酒吧,后面的大厅则作为用餐区。然而,这个空间在z轴上以天花板和地面之间的另一个分区为中心进行设计。如果由于餐厅空间活动的多变性而需要保持灵活性——包括两个座位、四个座位和六个座位,以及与聚会和其他活动有关的座位 相似文献
65.
Roberta Valmorbida Geovana D. Savi Juliana R. Silva Monica M.O. Yanez Carlos E.S. Soares Cristina Runtzel 《Food Additives and Contaminants: Part B: Surveillance Communications》2018,11(1):54-63
The quality and safety of maize (Zea mays L.) from different grain storage units (GSUs), located in the main producing region of Rondônia State, Northern Brazil, were evaluated. Maize grains (n = 76) stored in four GSUs were collected from July to November 2014 and evaluated for grain damages, humidity, fungi and fumonisins (FBs) content. The climate conditions data were also obtained from plant growing to storage periods. Regarding the moisture content and water activity (aw), these varied from 10.0% to 16.1% and 0.5 to 0.8, respectively. As expected, fungi spores were present in 94.8% of the samples, prevailing Fusarium genera, with a fungi colony maximum of 2.2 × 104 CFU g?1. Regarding FBs, 60.5% of the samples were contaminated, below Brazilian and United States maximum limits, but 9.2% had levels higher than the European legislation. 相似文献
66.
Gina Cavaliere Giovanna Trinchese Nadia Musco Federico Infascelli Chiara De Filippo Vincenzo Mastellone Valeria Maria Morittu Pietro Lombardi Raffaella Tudisco Micaela Grossi Vincenzo Monda Monica I. Cutrignelli Antonietta Messina Serena Calabrò Heleena B. Moni Luigi Stradella Giovanni Messina Marcellino Monda Maria Pina Mollica 《Journal of dairy science》2018,101(3):1843-1851
Excessive energy intake may evoke complex biochemical processes characterized by inflammation, oxidative stress, and impairment of mitochondrial function that represent the main factors underlying noncommunicable diseases. Because cow milk is widely used for human nutrition and in food industry processing, the nutritional quality of milk is of special interest with respect to human health. In our study, we analyzed milk produced by dairy cows fed a diet characterized by a high forage:concentrate ratio (high forage milk, HFM). In view of the low n-6:n-3 ratio and high content of conjugated linoleic acid of HFM, we studied the effects of this milk on lipid metabolism, inflammation, mitochondrial function, and oxidative stress in a rat model. To this end, we supplemented for 4 wk the diet of male Wistar rats with HFM and with an isocaloric amount (82 kJ, 22 mL/d) of milk obtained from cows fed a diet with low forage:concentrate ratio, and analyzed the metabolic parameters of the animals. Our results indicate that HFM may positively affect lipid metabolism, leptin:adiponectin ratio, inflammation, mitochondrial function, and oxidative stress, providing the first evidence of the beneficial effects of HFM on rat metabolism. 相似文献
67.
Silva Jefferson Kreutz Márcio Pereira Monica Costa-Abreu Marjory Da 《The Journal of supercomputing》2019,75(11):7573-7591
The Journal of Supercomputing - Due to the increasing number of cores in Systems on Chip (SoCs), bus architectures have suffered with limitations regarding performance. As applications demand... 相似文献
68.
Eshan Ganju Monica Prezzi Rodrigo Salgado Nayyar Zia Siddiki 《International Journal of Pavement Engineering》2018,19(11):966-975
The Dynamic Cone Penetrometer (DCP) is a device that is used in the construction industry for the assessment of in situ soil compaction quality. Over the past few decades, numerous correlations have been developed between the DCP test results and soil strength and stiffness parameters. This paper proposes a comprehensive set of criteria and recommendations for quality control (QC) of compacted subgrade that take into account the inherent statistical variability of DCP test results. For the development of the QC criteria, a new statistical methodology is used to extract representative test values from the raw field DCP test data. In order to use the proposed QC criteria, soils are first classified into two broad categories (fine-grained and coarse-grained) depending on their fabric and response to compaction efforts. Test results indicate that (i) for fine-grained soils, the DCP test values have good correlation with the plasticity index (PI), which is indicative of the type and amount of clay content of the soil and (ii) for coarse-grained soils, the DCP test values have good correlation with the optimum water content of the soil, which is directly related to its in situ density. DCP blow count correlation equations are presented for both soil categories. Recommendations for field DCP testing and data analysis are also provided to highlight the significance of the statistical distribution of the DCP test results in QC testing of compacted subgrade. 相似文献
69.
Alessandra Dellaquila Gabriele Greco Elisabetta Campodoni Mauro Mazzocchi Barbara Mazzolai Anna Tampieri Nicola M. Pugno Monica Sandri 《应用聚合物科学杂志》2020,137(22):48739
Silks have been widely used as biomaterials due to their biocompatibility, biodegradability, and excellent mechanical properties. In the present work, native spider silk was used as organic template for controlled nucleation of hydroxyapatite (HA) nano-coating that can act as biomimetic interface. Different bio-inspired neutralization methods and process parameters were evaluated to optimize the silk functionalization. The morphology and chemical composition were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analysis and mechanical properties were studied through tensile tests. Results showed that the optimized protocol enabled a controlled and homogeneous nucleation of apatite nano-crystals while maintaining silk mechanical performances after mineralization. This study reports the optimization of a simple and effective bio-inspired nucleation process for precise nucleation of HA onto spider silk templates, suitable to develop high-performance hybrid interfaces for bone tissue engineering. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48739. 相似文献
70.
Andrea Luca Tasca Eleonora Stefanelli Anna Maria Raspolli Galletti Riccardo Gori Gemma Mannarino Sandra Vitolo Monica Puccini 《化学工程与技术》2020,43(12):2382-2392
Hydrothermal carbonization of sewage sludge was carried out with the aim to evaluate the influence of process severity and initial solid content. Response surface methodology was applied to model yield and C yield responses. Enhanced dewaterability performance was recorded under mild processing conditions. The treatment promoted concentration and immobilization of Pb, Cd, Ni, Zn, and Cu. Variation of the solid content showed a stronger influence than severity on average yield and C yield. Higher heating values (HHVs) and energy retention efficiencies (EREs) of hydrochars obtained at the lowest solid content displayed the lowest values. Hence, the energy requirements of a first dewatering step should be compared with the related improvement in terms of HHV and ERE when sludge is used as feedstock. 相似文献