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501.
ZSM-11 zeolite samples differing by their active sites (H+ and different metal cations) have been studied in the transformation of ethane into aromatic hydrocarbons. A relationship between Lewis sites increasing–aromatization capacity and possible reaction steps have been suggested. 相似文献
502.
An experimental evaluation of theory-based mother and mother–child programs for children of divorce.
Wolchik Sharlene A.; West Stephen G.; Sandler Irwin N.; Tein Jenn-Yun; Coatsworth Douglas; Lengua Liliana; Weiss Lillie; Anderson Edward R.; Greene Shannon M.; Griffin William A. 《Canadian Metallurgical Quarterly》2000,68(5):843
This study evaluated the efficacy of 2 theory-based preventive interventions for divorced families: a program for mothers and a dual component mother–child program. The mother program targeted mother–child relationship quality, discipline, interparental conflict, and the father–child relationship. The child program targeted active coping, avoidant coping, appraisals of divorce stressors, and mother–child relationship quality. Families with a 9- to 12-year-old child (N ?=?240) were randomly assigned to the mother, dual-component, or self-study program. Postintervention comparisons showed significant positive program effects of the mother program versus self-study condition on relationship quality, discipline, attitude toward father–child contact, and adjustment problems. For several outcomes, more positive effects occurred in families with poorer initial functioning. Program effects on externalizing problems were maintained at 6-month follow-up. A few additive effects of the dual-component program occurred for the putative mediators; none occurred for adjustment problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
503.
Tabea Bartsch Claudia Arndt Liliana R. Loureiro Alexandra Kegler Edinson Puentes-Cala Javier Andrs Soto Biji T. Kurien Anja Feldmann Nicole Berndt Michael P. Bachmann 《International journal of molecular sciences》2021,22(21)
The anti-La mab 312B, which was established by hybridoma technology from human-La transgenic mice after adoptive transfer of anti-human La T cells, immunoprecipitates both native eukaryotic human and murine La protein. Therefore, it represents a true anti-La autoantibody. During maturation, the anti-La mab 312B acquired somatic hypermutations (SHMs) which resulted in the replacement of four aa in the complementarity determining regions (CDR) and seven aa in the framework regions. The recombinant derivative of the anti-La mab 312B in which all the SHMs were corrected to the germline sequence failed to recognize the La antigen. We therefore wanted to learn which SHM(s) is (are) responsible for anti-La autoreactivity. Humanization of the 312B ab by grafting its CDR regions to a human Ig backbone confirms that the CDR sequences are mainly responsible for anti-La autoreactivity. Finally, we identified that a single amino acid replacement (D > Y) in the germline sequence of the CDR3 region of the heavy chain of the anti-La mab 312B is sufficient for anti-La autoreactivity. 相似文献
504.
Liliana Krzystek Stanislaw Ledakowicz 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2000,75(12):1110-1118
This paper describes results of the application of simple metabolic model principles to aerobic growth of Kluyveromyces fragilis during the utilisation of a semi‐synthetic medium simulating dairy waste (whey). The theoretical yield coefficients (maximum, true and real) of biomass on lactose and oxygen, available electrons and ATP were determined and compared with experimental data. The experimental runs were performed in a B Brown fermenter (15 dm3 of operating capacity). The yeast K fragilis was cultured in semi‐synthetic medium containing lactose (40 g dm−3) as a main carbon and energy source and ammonia salts as a main nitrogen source (C/N = 8.74). The yeast growth is closely related to the concentration of oxygen in the media. The experimental yields of biomass on lactose and oxygen reached 94% and 88% of real maximum theoretical values, respectively. Calculated true biomass yield coefficients were closely correlated with the values resulting from the balance analysis of stoichiometric equations. The specific maintenance requirement (mATP) was 14.7 mmole ATP(g DM h)‐1. Determination of the elemental composition of the biomass during the course of fermentation resulted in observations of the cellular C/N ratio changes. The conversion of lactose carbon to biomass and CO2 was 74.3%–81.2%. The recovery of ATP reached 79%, and the recovery of oxygen 96.2%. © 2000 Society of Chemical Industry 相似文献
505.
A study of the carboxymethylation of wood pulp cellulose and cotton linters cellulose in different organic media, namely, ethanol, acetone, and ethanol-acetone mixtures, is performed. Previously, the ethanol-acetone 1 : 1 (w/w) mixture used as reaction medium was found to give a higher degree of substitution (DS) than the pure solvents separately. In the present work, the kinetic investigation of cellulose carboxymethylation was carried out in ethanol-acetone 3 : 7 (w/w) mixture, as well as in acetone as reaction media, and the same synergistic effect of the solvents mixture was observed. The data suggested a pseudo-first-order kinetic behavior satisfactorily described by the following equation: ln(1.11 − DS) = −kt. The two reaction steps observed are related to the transformations of less ordered regions with higher reaction rate and more ordered regions with smaller reaction rates, respectively. A possible explanation for this behaviour is given, taking into account the different structural changes of cellulose crystallinity and accessibility produced by ethanol-acetone 3 : 7 (w/w) mixture, ethanol, and acetone, as revealed by X-ray diffraction and calorimetry determinations. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: 481–486, 1998 相似文献
506.
Luis Rodríguez Francisco P. Chvez Maria E. Gonzlez Liliana Basabe Tanilo Rivero 《Yeast (Chichester, England)》1998,14(15):1399-1406
The URA3 gene of Candida utilis encoding orotidine-5′-phosphate decarboxylase enzyme was isolated by complementation in Escherichia coli pyrF mutation. The deduced amino-acid sequence is highly similar to that of the Ura3 proteins from other yeast and fungal species. An extensive analysis of the family of orotidine-5′-phosphate decarboxylase is shown. The URA3 gene of C. utilis was able to complement functionally the ura3 mutation of Saccharomyces cerevisiae. The sequence presented here has been deposited in the EMBL data library under Accession Number Y12660. © 1998 John Wiley & Sons, Ltd. 相似文献
507.
Farnaz Ghorbani Theresa Reiter Liliana Liverani Dirk W. Schubert Aldo R. Boccaccini Judith A. Roether 《Advanced Engineering Materials》2023,25(6):2201103
Electrospinning is a promising approach for the development of fibrous tissue engineering (TE) scaffolds suitable for hard and soft tissues. Apart from physicomechanical properties, electrospun fibers are required to incorporate bioactive cues to control cellular functions, including facilitating biomineralization and osteogenic differentiation in case of bone TE, as well as vascularization, to support successful tissue regeneration. In recent years, bioactive glass (BG) addition to electrospun biopolymer fibers has shown promising results in enhancing the properties of fibers, including the improvement of biological performance. In this article, a comprehensive overview of BG-containing electrospun polymer composite fibers is presented, identifying the parameters that affect the mechanical properties as well as the biological response in vivo and in vitro. Subsequently, the effects of BG addition on the properties of the scaffolds are discussed. Recent developments in the fields of bone regeneration, wound healing, and drug delivery using BG-containing electrospun fibrous scaffolds are described in detail. Essential aspects related to BG-polymer composite fibers for translational research in TE are highlighted for future research in this field. 相似文献
508.
Vanessa Pereira Perez Alonso Maria Paula M. B. B. Gonçalves Francisca Airlane Esteves de Brito Giovana Rueda Barboza Liliana de Oliveira Rocha Nathalia Cristina Cirone Silva 《Comprehensive Reviews in Food Science and Food Safety》2023,22(1):688-713
Bacterial biofilm formation in low moisture food processing (LMF) plants is related to matters of food safety, production efficiency, economic loss, and reduced consumer trust. Dry surfaces may appear dry to the naked eye, however, it is common to find a coverage of thin liquid films and microdroplets, known as microscopic surface wetness (MSW). The MSW may favor dry surface biofilm (DSB) formation. DSB formation is similar in other industries, it occurs through the processes of adhesion, production of extracellular polymeric substances, development of microcolonies and maturation, it is mediated by a quorum sensing (QS) system and is followed by dispersal, leading to disaggregation. Species that survive on dry surfaces develop tolerance to different stresses. DSB are recalcitrant and contribute to higher resistance to sanitation, becoming potential sources of contamination, related to the spoilage of processed products and foodborne disease outbreaks. In LMF industries, sanitization is performed using physical methods without the presence of water. Although alternative dry sanitizing methods can be efficiently used, additional studies are still required to develop and assess the effect of emerging technologies, and to propose possible combinations with traditional methods to enhance their effects on the sanitization process. Overall, more information about the different technologies can help to find the most appropriate method/s, contributing to the development of new sanitization protocols. Thus, this review aimed to identify the main characteristics and challenges of biofilm management in low moisture food industries, and summarizes the mechanisms of action of different dry sanitizing methods (alcohol, hot air, UV-C light, pulsed light, gaseous ozone, and cold plasma) and their effects on microbial metabolism. 相似文献
509.
Liliana Grazina Isabel Mafra Linda Monaci Joana S. Amaral 《Comprehensive Reviews in Food Science and Food Safety》2023,22(5):3870-3909
Dietary supplements are legally considered foods despite frequently including medicinal plants as ingredients. Currently, the consumption of herbal dietary supplements, also known as plant food supplements (PFS), is increasing worldwide and some raw botanicals, highly demanded due to their popularity, extensive use, and/or well-established pharmacological effects, have been attaining high prices in the international markets. Therefore, botanical adulteration for profit increase can occur along the whole PFS industry chain, from raw botanicals to plant extracts, until final PFS. Besides the substitution of high-value species, unintentional mislabeling can happen in morphologically similar species. Both cases represent a health risk for consumers, prompting the development of numerous works to access botanical adulterations in PFS. Among different approaches proposed for this purpose, mass spectrometry (MS)-based techniques have often been reported as the most promising, particularly when hyphenated with chromatographic techniques. Thus, this review aims at describing an overview of the developments in this field, focusing on the applications of MS-based techniques to targeted and untargeted analysis to detect botanical adulterations in plant materials, extracts, and PFS. 相似文献
510.
Soberanis M. A. Escalante Vales-Pinzón Caridad Hernández-Núñez Emanuel Flota-Bañuelos Manuel Medina J. Quintal-Palomo R. San-Pedro Liliana Ruiz-Gómez Miguel 《Clean Technologies and Environmental Policy》2023,25(1):35-49
Clean Technologies and Environmental Policy - Hydrogen (H2) is an energy carrier capable of replacing fossil fuels without the main effect of combustion-based pollutant generation into the... 相似文献