全文获取类型
收费全文 | 1460篇 |
免费 | 106篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 421篇 |
金属工艺 | 39篇 |
机械仪表 | 35篇 |
建筑科学 | 59篇 |
矿业工程 | 3篇 |
能源动力 | 32篇 |
轻工业 | 379篇 |
水利工程 | 12篇 |
石油天然气 | 5篇 |
无线电 | 80篇 |
一般工业技术 | 183篇 |
冶金工业 | 63篇 |
原子能技术 | 8篇 |
自动化技术 | 241篇 |
出版年
2024年 | 9篇 |
2023年 | 13篇 |
2022年 | 32篇 |
2021年 | 85篇 |
2020年 | 52篇 |
2019年 | 54篇 |
2018年 | 54篇 |
2017年 | 51篇 |
2016年 | 76篇 |
2015年 | 44篇 |
2014年 | 70篇 |
2013年 | 116篇 |
2012年 | 102篇 |
2011年 | 102篇 |
2010年 | 91篇 |
2009年 | 76篇 |
2008年 | 64篇 |
2007年 | 50篇 |
2006年 | 51篇 |
2005年 | 50篇 |
2004年 | 37篇 |
2003年 | 45篇 |
2002年 | 29篇 |
2001年 | 13篇 |
2000年 | 22篇 |
1999年 | 22篇 |
1998年 | 12篇 |
1997年 | 15篇 |
1996年 | 7篇 |
1995年 | 6篇 |
1994年 | 12篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 6篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1976年 | 5篇 |
1975年 | 3篇 |
1974年 | 5篇 |
1970年 | 5篇 |
排序方式: 共有1569条查询结果,搜索用时 234 毫秒
61.
Marcela L. Martínez Ma. Gabriela Bordón Rebeca L. Lallana Pablo D. Ribotta Damián M. Maestri 《Food and Bioprocess Technology》2017,10(6):1113-1121
Box-Behnken designs were used to optimize a process for sesame oil extraction by screw-pressing at low temperature (50 °C). Experimental designs included seed moisture content (SMC), pressing speed (PS), and restriction die (RD) as the main processing parameters. Extractions at pilot plant scale showed a peak in oil recovery (OR, 71.1 ± 2.80%) at 12.3% SMC, 4 mm RD, and 20 rpm PS. Theoretical models were scanned against experimental data in order to scale up the proposed oil extraction process to industrial scale. A fitted model for OR showed a maximum predicted value similar to the highest experimental value (74.4 ± 1.23%) under the following conditions: 8.03% SMC, 10 mm RD, and 20 rpm PS. Chemical quality parameters of oils obtained at both pilot and industrial scales were in the ranges stated in Codex (FAO/WHO) standards for non-refined sesame oil. 相似文献
62.
Alberto Abad Anna Pompili Angela Costa Isabel Trancoso José Fonseca Gabriela Leal Luisa Farrajota Isabel P. Martins 《Computer Speech and Language》2013,27(6):1235-1248
One of the most common effects among aphasia patients is the difficulty to recall names or words. Typically, word retrieval problems can be treated through word naming therapeutic exercises. In fact, the frequency and the intensity of speech therapy are key factors in the recovery of lost communication functionalities. In this sense, speech and language technology can have a relevant contribution in the development of automatic therapy methods. In this work, we present an on-line system designed to behave as a virtual therapist incorporating automatic speech recognition technology that permits aphasia patients to perform word naming training exercises. We focus on the study of the automatic word naming detector module and on its utility for both global evaluation and treatment. For that purpose, a database consisting of word naming therapy sessions of aphasic Portuguese native speakers has been collected. In spite of the different patient characteristics and speech quality conditions of the collected data, encouraging results have been obtained thanks to a calibration method that makes use of the patients’ word naming ability to automatically adapt to the patients’ speech particularities. 相似文献
63.
64.
65.
Hayane Ferreira Leite Ladislau Thaísa Gabriela Silva de Farias Bruna Lúcia Mendonça Soares José Alberto da Costa Medeiros Natália Ferrão Castelo Branco Melo Thatiana Montenegro Stamford–Arnaud Thayza Christina Montenegro Stamford Tânia Lucia Montenegro Stamford 《International Journal of Food Science & Technology》2021,56(10):5395-5401
This research verified the ability of Lactobacillus rhamnosus encapsulated with inulin to tolerate the simulated digestive system and their viability in a soy blend. Probiotic encapsulated in alginate-chitosan matrix without inulin presented a better encapsulation efficiency (80.92%) than encapsulation with inulin (57.39%). On the 28th day, the count of probiotics decreased by 3.42 and 1.99 logarithmic cycles of free and encapsulated cells without inulin, respectively. In contrast, the microorganisms encapsulated with inulin showed an increase of 1.26 logs CFU g−1. During gastrointestinal simulation, cell counts decreased by 0.78, 1.55 and 1.95 CFU g−1 logs for encapsulated cells without inulin, free and encapsulated with inulin, respectively. Sensory panellists liked the fermented soy blend with encapsulated lactobacilli, and this result shows the possibility to create new probiotic foods of plant origin. Therefore, the alginate/chitosan matrix can be considered adequate for the encapsulation of L. rhamnosus. The inulin reduces the encapsulation efficiency and increases the cell loss in gastrointestinal simulation. Considering cellular losses, the best option for preparing a fermented soy blend is to use L. rhamnosus encapsulated without inulin. 相似文献
66.
Mohammad Alrosan Thuan-Chew Tan Azhar Mat Easa Sana Gammoh Stan Kubow Muhammad H. Alu'datt 《International Journal of Food Science & Technology》2022,57(4):2039-2050
There has been a growing interest in plant proteins due to their beneficial health effects, low cost and variety of applications in food industries. The low solubility of lentil proteins (LPs) is one of the significant factors that limit their use in food applications. Quinoa proteins (QPs), which have high water solubility, were combined with LPs at pH 12 to generate LP-QP complexes to generate pH-based soluble protein compounds. The LP-QP complexes demonstrated a large surface charge with an increase solubilisation of the protein complexes by more than 85%, together with resistance to protein aggregation. The combination of LPs to QPs led to a significant increase (P < 0.05) in unique tertiary and secondary protein structures as determined by the protein–protein interaction (PPI) technique involving pH recycling. Interactions between LPs and QPs affected the surface morphology of the protein complexes formed. Electrostatic interactions, hydrophobic forces and hydrogen bonding were indicated to play key roles in the PPIs. The capacity of pH cycling to illustrate the above protein interactions shows that this is a robust approach for assessing the emulsion and foaming properties of food proteins. 相似文献
67.
68.
Carine Viana Gabriela M. Zemolin Larissa S. Müller Thaís R. Dal Molin Helena Seiffert Leandro M. de Carvalho 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(1):1-9
Methyl-xanthines and adrenergic stimulants, such as caffeine and synephrine, are commonly added to food supplements due to their stimulating and thermogenic effects. In addition, the abusive consumption of food supplements with ergogenic and aesthetic purposes has been observed worldwide. This work describes the study of caffeine, p-synephrine, hordenine, octopamine, tyramine, ephedrine and salicin as stimulants in dietary supplements marketed in Brazil for weight loss and physical fitness claims. A total of 94 different products were acquired from 30 Brazilian websites. Thus, the sampling of marketed supplements was performed in virtual commerce (e-commerce) with claims of weight loss, appetite reduction, fat burning and metabolism acceleration. The developed analytical method involved the separation of the stimulants by HPLC with diode array detection (HPLC-DAD) by using a gradient elution of flow rate (0.7–2.5 ml min?1) and mobile phase composition (0.1% H3PO4/methanol). The validated method was applied to the study of 46 dietary supplements. Caffeine, p-synephrine and ephedrine were found to be present as stimulants in 52% of the studied samples marketed as encapsulated or bulk forms. Caffeine was found to be present in concentrations that represent doses from 25.0 to 1476.7 mg day–1. Synephrine was found in concentrations that represent doses from 59.1 to 127.0 mg day–1. Ephedrine was found to be associated with caffeine in one formulation at a concentration representing a 26.1 mg day–1 dosage. 相似文献
69.
Elisa Franzoni Barbara Pigino Gabriela Graziani Claudio Lucchese Alberto Fregni 《Materials and Structures》2016,49(4):1527-1542
Given the high energy consumption connected to old buildings and their large environmental impact, there is a strong need for effective solutions for the building envelope retrofitting. Among these solutions, external thermal insulation composite systems (ETICS) have found large application in recent decades. In this paper a new kind of large-size thermal insulation composite boards, prefabricated using porcelain stoneware slab finishing, was developed. Different thermal insulating materials and adhesives, with and without glass fibre mesh, were tested by both current methodologies and purposely designed tests, in order to assess their physical–mechanical properties and durability performance, finally selecting the most suitable materials for the composite board. The strong points of this composite board are mainly: (i) its short placing time and improved execution quality, due to prefabrication; (ii) its high aesthetical value; (iii) its high durability, as the finishing layer is mostly insensible to weathering. The results highlight the good performances of the prefabricated composite board developed in this study (generally higher than current ETICS). The testing procedure followed in this study is also meant to give a contribution to the establishment of methodologies for the selection and durability assessment of materials for the building envelope retrofitting. 相似文献