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排序方式: 共有2135条查询结果,搜索用时 15 毫秒
61.
62.
Wang Tao Semenov Sergey Wang Engang Delannoy Yves Fautrelle Yves Budenkova Olga 《Metallurgical and Materials Transactions B》2019,50(6):3039-3054
Metallurgical and Materials Transactions B - Modeling of equiaxed solidification is vital for understanding the solidification process of metallic alloys. In this work, an extended literature... 相似文献
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65.
Josiah Ochieng Olga Y. Korolkova Guoliang Li Renjie Jin Zhenbang Chen Robert J. Matusik Samuel Adunyah Amos M. Sakwe Olugbemiga Ogunkua 《International journal of molecular sciences》2022,23(7)
The present studies were conducted to evaluate key serum proteins and other components that mediate anchorage-independent growth (3-D growth) of LNCaP prostate cancer cells as spheroids. The cells were cultured on ultra-low attachment plates in the absence and presence of fetuin-A and with or without extracellular vesicles. The data show that fetuin-A (alpha 2HS glycoprotein) is the serum protein that mediates 3-D growth in these cells. It does so by sequestering extracellular vesicles of various sizes on the surfaces of rounded cells that grow as spheroids. These vesicles in turn transmit growth signals such as the activation of AKT and MAP kinases in a pattern that differs from the activation of these key growth signaling pathways in adherent and spread cells growing in 2-D. In the process of orchestrating the movement and disposition of extracellular vesicles on these cells, fetuin-A is readily internalized in adhered and spread cells but remains on the surfaces of non-adherent cells. Taken together, our studies suggest the presence of distinct signaling domains or scaffolding platforms on the surfaces of prostate tumor cells growing in 3-D compared to 2-D. 相似文献
66.
Comprehensive Review of Patulin Control Methods in Foods 总被引:1,自引:0,他引:1
Matthew M. Moake Olga I. Padilla‐Zakour Randy W. Worobo 《Comprehensive Reviews in Food Science and Food Safety》2005,4(1):8-21
The mycotoxin, patulin (4‐hydroxy‐4H‐furo [3, 2c] pyran‐2[6H]‐one), is produced by a number of fungi common to fruit‐ and vegetable‐based products, most notably apples. Despite patulin's original discovery as an antibiotic, it has come under heavy scrutiny for its potential negative health effects. Studies investigating these health effects have proved inconclusive, but there is little doubt as to the potential danger inherent in the contamination of food products by patulin. The danger posed by patulin necessitates its control and removal from foods products, creating a demand for handling and processing techniques capable of doing so, preferably at low cost to industry. With this being the case, much research has been devoted to understanding the basic chemical and biological nature of patulin, as well as its interaction within foods and food production. While past resarch has elucidated a great deal, patulin contamination continues to be a challenge for athe food industry. Here, we review in depth the past research on patulin with an emphasis upon its influence within the food industry, including its regulation, health effects, biosynthesis, detection, quantification, distribution within foods, and control, during the various stages of apple juice production. Finally, key areas where future patulin research should focus to best control the patulin contamination problem within the food industry are addressed. 相似文献
67.
Isabel Odriozola‐Serrano Robert Soliva‐Fortuny Olga Martín‐Belloso 《Journal of the science of food and agriculture》2008,88(15):2606-2614
BACKGROUND: The feasibility of using modified atmosphere packaging (5 kPa O2 + 5 kPa CO2) to maintain the antioxidant properties of fresh‐cut tomatoes during shelf‐life was assessed through storage at different temperatures (5, 10, 15 and 20 °C). Health‐related compounds, antioxidant capacity, microbiological counts, physicochemical parameters and in‐package atmosphere of tomato slices were determined. RESULTS: Initial lycopene, vitamin C and phenolic contents and physicochemical parameters of tomato slices were well maintained for 14 days at 5 °C. Lycopene and total phenolic contents were enhanced over time in tomato slices stored at 15 and 20 °C. However, this increase in antioxidant compounds of fresh‐cut tomatoes during storage may be associated with excessive amounts of CO2 (R2 = 0.5679–0.7328) in the packages due to microbial growth. Although keeping tomato slices at temperatures above 10 °C increased their antioxidant content, the shelf‐life of the product was reduced by up 4 days. CONCLUSIONS: A storage temperature of 5 °C is appropriate for maintaining the microbiological shelf‐life of fresh‐cut tomatoes for up to 14 days and also allows the antioxidant properties of tomato slices to be retained over this period, thus reducing wounding stress and deteriorative changes. Copyright © 2008 Society of Chemical Industry 相似文献
68.
众多植物多糖中,阿拉伯半乳聚糖对嗜黏蛋白阿克曼菌(Akkermansia muciniphila,Akk)模式菌株(DSM 22959)的促生长效果最佳.为进一步探究阿拉伯半乳聚糖对Akk代谢物的影响,本研究将阿拉伯半乳聚糖作为部分碳源对Akk进行体外发酵培养,确定了阿拉伯半乳聚糖的补充量以便于Akk发酵液样本的后续分... 相似文献
69.
Weronika
liewska Katarzyna Struszczyk-
wita Olga Marchut-Mikoajczyk 《International journal of molecular sciences》2022,23(8)
Salty environments are widely known to be inhospitable to most microorganisms. For centuries salt has been used as a food preservative, while highly saline environments were considered uninhabited by organisms, and if habited, only by prokaryotic ones. Nowadays, we know that filamentous fungi are widespread in many saline habitats very often characterized also by other extremes, for example, very low or high temperature, lack of light, high pressure, or low water activity. However, fungi are still the least understood organisms among halophiles, even though they have been shown to counteract these unfavorable conditions by producing multiple secondary metabolites with interesting properties or unique biomolecules as one of their survival strategies. In this review, we focused on biomolecules obtained from halophilic filamentous fungi such as enzymes, pigments, biosurfactants, and osmoprotectants. 相似文献
70.
Luciano J. Quitão-Teixeira Ingrid Aguiló-Aguayo Afonso M. Ramos Olga Martín-Belloso 《Food and Bioprocess Technology》2008,1(4):364-373
The effects of high-intensity pulsed electric fields (HIPEF) on oxidative enzymes and color of fresh carrot juice were studied.
A response surface methodology (RSM) was used to evaluate the effect of pulse polarity (mono or bipolar mode), pulse width
(from 1 to 7 μs), and pulse frequency (from 50 to 250 Hz) on color and peroxidase (POD) inactivation of carrot juice treated
by HIPEF. The total treatment time and the electric field strength were set at 1,000 μs and 35 kV/cm, respectively, at a temperature
below 35°C. The physicochemical characteristics of carrot juice were measured. There was a linear relationship between electrical
conductivity and temperature of the carrot juice. The results showed that HIPEF-treated carrot juice at 35 kV/cm for 1,000 μs
applying 6 μs pulse width at 200 Hz in bipolar mode led to 73.0% inactivation of POD. The color coordinates did not change
significantly. Therefore, HIPEF was effective in POD inactivation and carrot juice color preservation. 相似文献