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161.
Clara Llorens-Quintana Maryam Mousavi Dorota Szczesna-Iskander D. Robert Iskander 《Contact lens & anterior eye》2018,41(1):18-22
Purpose
To evaluate the effect of two types of daily contact lenses (delefilcon A and omafilcon A) on the tear film and establish whether it is dependent on pre-corneal tear film characteristics using a new method to analyse high-speed videokeratoscopy recordings, as well as to determine the sensitivity of the method in differentiating between contact lens materials on eye.Methods
High-speed videokeratoscopy recordings were analysed using a custom made automated algorithm based on a fractal dimension approach that provides a set of parameters directly related to tear film stability. Fifty-four subjects participated in the study. Baseline measurements, in suppressed and natural blinking conditions, were taken before subjects were fitted with two different daily contact lenses and after four hours of contact lens wear.Results
The method for analysing the stability of the tear film provides alternative parameters to the non-invasive break up time to assess the quality of the pre-corneal and pre-lens tear film. Both contact lenses significantly decreased the quality of the tear film in suppressed and natural blinking conditions (p<0.001). The utilised method was able to distinguish between contact lens materials on eye in suppressed blinking conditions. The pre-corneal tear film characteristics were not correlated with the decrease in pre-lens tear film quality.Conclusion
High-speed videokeratoscopy equipped with an automated method to analyse the dynamics of the tear film is able to distinguish between contact lens materials in vivo. Incorporating the assessment of pre-lens tear film to the clinical practice could aid improving contact lens fitting and understand contact lens comfort. 相似文献162.
Bianca Cristina Nogueira Fernandes Bruna Barbon Paulo Maria Clara Guimarães Claire Isabel Grigoli de Luca Sarantopoulos Nathália Ramos de Melo Ana Silvia Prata 《Comprehensive Reviews in Food Science and Food Safety》2022,21(3):2309-2334
Food safety and extended shelf life linked to convenience were the major reasons for the development of the packaging field. However, advances in material science and the widespread encapsulation technologies are allowing the establishment of new concepts for packages, such as intelligent and active packages. Particulate systems have been developed in recent years for the most diverse area with several purposes that can be employed to improve packaging performance mainly focusing on the modification of barrier properties. This review analyzes the recent developments using encapsulation in food packaging and the main concepts about mass transfer evolved in the functionality of these packages, as well as discusses the research challenges faced by the food packaging sector. 相似文献
163.
Cristina Montealegre Clara Esteve Maria Concepción García Carmen García-Ruiz Maria Luisa Marina 《Critical reviews in food science and nutrition》2014,54(5):611-624
This paper is a comprehensive review grouping the information on the extraction, characterization, and quantitation of olive and olive oil proteins and providing a practical guide about these proteins. Most characterized olive proteins are located in the fruit, mainly in the seed, where different oleosins and storage proteins have been found. Unlike the seed, the olive pulp contains a lower protein content having been described a polypeptide of 4.6 kDa and a thaumain-like protein. Other important proteins studied in olive fruits have been enzymes which could play important roles in olives characteristics. Part of these proteins is transferred from the fruit to the oil during the manufacturing process of olive oil. In fact, the same polypeptide of 4.6 kDa found in the pulp has been described in the olive oil and, additionally, the presence of other proteins and enzymes have also been described. Protein profiles have recently been proposed as an interesting strategy for the varietal classification of olive fruits and oils. Nevertheless, there is still a lot of knowledge without being explored requiring new studies focused on the determination and characterization of these proteins. 相似文献
164.
Biochemical and Visual Changes in Cactus Stems (Opuntia ficus‐indica Mill.) Stored at 4, 12 and 26C
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Lizette Liliana Rodríguez‐Verástegui Juliana Osorio‐Córdoba Fernando Díaz de León‐Sánchez Clara Pelayo‐Zaldívar David Manuel Díaz‐Pontones Elsa Bosquez‐Molina Guadalupe Judith Márquez‐Guzmán Héctor Bernardo Escalona‐Buendía José Ramón Verde‐Calvo Laura Josefina Pérez‐Flores 《Journal of Food Biochemistry》2015,39(4):449-461
165.
Maria L Gonzlez-San Jos Luis J R Barron Clara Díez 《Journal of the science of food and agriculture》1990,51(3):337-343
In general, the anthocyanin content of grapes increases during ripening but presents a concentration minimum a few days before physiological maturity. This minimum is sharper for the acyl derivatives. Significant behavioural differences were found between monoglucosides and their acyl derivatives. A polynomial model was used to describe the evolution of anthocyanins in the maturation of Tempranillo grapes (Vitis vinifera L). 相似文献
166.
Clara M. Szlavko 《Journal of the Institute of Brewing》1973,79(4):283-288
A gas chromatographic method is presented for routine quantitative analysis of aromatic higher alcohols in beer. A satisfactory overall order of reproducibility, sensitivity and simplicity was achieved under the conditions described. This method has been used to compare finished Canadian ales and lagers. It was possible to differentiate an ale from a lager fermentation by the tryptophol content of the product. Experiments were conducted to investigate the influence of several factors on the concentration levels of aromatic higher alcohols. These compounds are produced by the yeast during fermentation and the levels achieved depend upon the type of yeast used, the fermentation conditions, and differences in the wort fermented. 相似文献
167.
Food packaging based on polymer nanomaterials 总被引:6,自引:0,他引:6
Clara Silvestre Donatella Duraccio Sossio Cimmino 《Progress in Polymer Science》2011,36(12):1766-1782
Since its starting in the 19th century, modern food packaging has made great advances as results of global trends and consumer preferences. These advances are oriented to obtain improved food quality and safety. Moreover, with the move toward globalization, food packaging requires also longer shelf life, along with the monitoring of safety and quality based upon international standards. Nanotechnology can address all these requirements and extend and implement the principal packaging functions - containment, protection and preservation, marketing and communications. Applications of polymer nanotechnology in fact can provide new food packaging materials with improved mechanical, barrier and antimicrobial properties, together with nano-sensors for tracing and monitoring the condition of food during transport and storage.The latest innovations in food packaging, using improved, active and smart nanotechnology will be analyzed. It will be also discuss the limits to the development of the new polymer nanomaterials that have the potential to completely transform the food packaging industry. 相似文献
168.
A heat-induced O/W emulsion gel that undergoes a phase transition from sol to gel on heating was formed from the addition of aqueous HCl to a toluene solution of a long-chain amidoamine derivative (C18AA). The heat induced O/W emulsions are highly sensitive to temperature, and the sol-gel transition temperature could be simply controlled by adjusting the C18AA concentration. Interestingly, the sol-gel transition of the O/W emulsions was also very sensitive to pH. Thus, we have successfully prepared a novel double-stimuli responsive gel based on O/W emulsions consisting of C18AA and HCl. 相似文献
169.
An Advanced Colour Calibration Method for Fish Freshness Assessment: a Comparison Between Standard and Passive Refrigeration Modalities 总被引:1,自引:0,他引:1
Corrado Costa Francesca Antonucci Paolo Menesatti Federico Pallottino Clara Boglione Stefano Cataudella 《Food and Bioprocess Technology》2013,6(8):2190-2195
Freshness represents a pivotal aspect in fish product for both security and quality. Its evaluation still represents the key factor driving the consumer’ choices. Fish appearance is affected by many different factors that demand the contribution of different disciplines to be understood: from the physical and optical properties to the slaughtering and post-slaughtering conditions. An innovative preservation system is represented by the Passive Refrigeration PRS? developed for the preservation and transport of perishable food products. Scientific methods for product freshness evaluation may be conveniently divided into two categories: sensorial and instrumental. In this study, an instrumental method of colour calibration and discrimination is proposed at pilot scale for automatic evaluation of gilthead seabream (Sparus aurata) freshness. We propose a non-destructive method based on the colorimetric imaging of the whole external body of seabreams to evaluate through multivariate partial least squares which approach the differences in the freshness preservation under four refrigeration modalities. The matrix of the independent variables is represented by RGB values for each pixel belonging to an extracted region of interest (129,633 values). The dependent variable is composed by two dummy variable corresponding to fresh (T0) or non-fresh (T2) individuals. T1 individuals were used as external test. The results quantified significant colorimetric differences between fresh and non-fresh fish. All fish used to create the model (T0 and T2) were correctly classified as fresh or non-fresh, while external test individuals (T1) were all classified as fresh. The proposed imaging method merges different image analysis techniques: (a) colorimetric calibration, (b) morphometric superimposition and (c) partial least square discriminant analysis modelling. This innovative and non-destructive approach allows the automatic assessment of fish freshness. 相似文献
170.