全文获取类型
收费全文 | 517篇 |
免费 | 40篇 |
专业分类
电工技术 | 8篇 |
综合类 | 1篇 |
化学工业 | 185篇 |
金属工艺 | 4篇 |
机械仪表 | 3篇 |
建筑科学 | 25篇 |
矿业工程 | 2篇 |
能源动力 | 6篇 |
轻工业 | 99篇 |
水利工程 | 2篇 |
无线电 | 41篇 |
一般工业技术 | 79篇 |
冶金工业 | 49篇 |
原子能技术 | 3篇 |
自动化技术 | 50篇 |
出版年
2023年 | 7篇 |
2022年 | 41篇 |
2021年 | 51篇 |
2020年 | 22篇 |
2019年 | 13篇 |
2018年 | 14篇 |
2017年 | 18篇 |
2016年 | 21篇 |
2015年 | 25篇 |
2014年 | 24篇 |
2013年 | 28篇 |
2012年 | 25篇 |
2011年 | 31篇 |
2010年 | 24篇 |
2009年 | 14篇 |
2008年 | 21篇 |
2007年 | 18篇 |
2006年 | 16篇 |
2005年 | 14篇 |
2004年 | 3篇 |
2003年 | 8篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 8篇 |
1997年 | 6篇 |
1996年 | 7篇 |
1994年 | 12篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 8篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1984年 | 2篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 7篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1967年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有557条查询结果,搜索用时 15 毫秒
21.
Veronika Hefka Blahnov Lucy Vojtov Veronika Pavlikov Johana Muchov Eva Filov 《International journal of molecular sciences》2022,23(8)
Collagen I-based foams were modified with calcined or noncalcined hydroxyapatite or calcium phosphates with various particle sizes and pores to monitor their effect on cell interactions. The resulting scaffolds thus differed in grain size, changing from nanoscale to microscopic, and possessed diverse morphological characteristics and resorbability. The materials’ biological action was shown on human bone marrow MSCs. Scaffold morphology was identified by SEM. Using viability test, qPCR, and immunohistochemical staining, we evaluated the biological activity of all of the materials. This study revealed that the most suitable scaffold composition for osteogenesis induction is collagen I foam with calcined hydroxyapatite with a pore size of 360 ± 130 µm and mean particle size of 0.130 µm. The expression of osteogenic markers RunX2 and ColI mRNA was promoted, and a strong synthesis of extracellular protein osteocalcin was observed. ColI/calcined HAP scaffold showed significant osteogenic potential, and can be easily manipulated and tailored to the defect size, which gives it great potential for bone tissue engineering applications. 相似文献
22.
Resistant starch (RS) included in pasta can have auspicious health benefits and functional properties. The resistance of starch,
however, can be greatly influenced by the applied food preparation process. The aim of the present study was to investigate
the effects of two different resistant starches on the digestibility of pasta and to predict the impact of the conventional
pasta processing (extrusion under standard conditions, 120 bars, 40°C; drying in an air-drying room at 35–40°C and cooking
until the optimum cooking time) on the quality of different resistant starch included in products by using an in vitro enzymatic
hydrolysis method. Results showed that the applied, conventional pasta extrusion step had only a small effect on the liberated
glucose level and did not influence the RS content significantly. The cooking in contrast caused an increased digestibility
and the lost of resistance of all pasta products. The digestibility was significantly lower (p < 0.05) in the case of raw and dried samples compared to the cooked pastas. It can be concluded that the resistant starches
used in the samples are heat sensitive and their properties change radically during the pasta preparation, mainly during cooking. 相似文献
23.
Dr. Veronika Papoušková Dr. Pavel Kadeřávek Olga Otrusinová Alžbeta Rabatinová Dr. Hana Šanderová Jiří Nováček Dr. Libor Krásný Prof. Vladimír Sklenář Dr. Lukáš Žídek 《Chembiochem : a European journal of chemical biology》2013,14(14):1772-1779
The partially disordered δ subunit of RNA polymerase was studied by various NMR techniques. The structure of the well‐folded N‐terminal domain was determined based on inter‐proton distances in NOESY spectra. The obtained structural model was compared to the previously determined structure of a truncated construct (lacking the C‐terminal domain). Only marginal differences were identified, thus indicating that the first structural model was not significantly compromised by the absence of the C‐terminal domain. Various 15N relaxation experiments were employed to describe the flexibility of both domains. The relaxation data revealed that the C‐terminal domain is more flexible, but its flexibility is not uniform. By using paramagnetic labels, transient contacts of the C‐terminal tail with the N‐terminal domain and with itself were identified. A propensity of the C‐terminal domain to form β‐type structures was obtained by chemical shift analysis. Comparison with the paramagnetic relaxation enhancement indicated a well‐balanced interplay of repulsive and attractive electrostatic interactions governing the conformational behavior of the C‐terminal domain. The results showed that the δ subunit consists of a well‐ordered N‐terminal domain and a flexible C‐terminal domain that exhibits a complex hierarchy of partial ordering. 相似文献
24.
Kamil Musilek Dr. Ondrej Holas Jan Misik Miroslav Pohanka Dr. Ladislav Novotny Vlastimil Dohnal Dr. Veronika Opletalova Kamil Kuca Dr. 《ChemMedChem》2010,5(2):247-254
Acetylcholinesterase (AChE) reactivators are crucial antidotes to organophosphate intoxication. A new series of 26 monooxime‐monocarbamoyl xylene‐linked bispyridinium compounds was prepared and tested in vitro, along with known reactivators (pralidoxime, HI‐6, obidoxime, trimedoxime, methoxime, K107, K108 and K203), on a model of tabun‐ and paraoxon‐, methylparaoxon‐ and DFP‐inhibited human erythrocyte AChE. Although their ability to reactivate tabun‐inhibited AChE did not exceed that of the previously known compounds, some newly prepared compounds showed promising reactivation of pesticide‐inhibited AChE. The acute toxicity of the novel compounds was also determined. Docking studies using tabun‐inhibited AChE were performed for three compounds of interest. The structure–activity relationship (SAR) study confirmed the apparent influence of the xylene linkage and carbamoyl moiety on the reactivation ability and toxicity of the agents. 相似文献
25.
26.
Veronika Kaufmann Siegfrid Scherer Ulrich Kulozik 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,5(42):59-64
Die ESL-Technologie stellt nach der H-Milch eine weitere Entwicklung mit hohem Zusatznutzen in Bezug auf Haltbarkeit und Vorratshaltung
dar, wovon sowohl Handel als auch Verbraucher gleicherma?en profitieren k?nnen. Im Vergleich zum herk?mmlich pasteurisierten
Produkt bringt das ESL-Konzept entscheidende Vorteile hinsichtlich der Haltbarkeit der Milch mit sich, wirkt sich dabei aber
kaum oder nur geringfügig auf die für den Verbraucher entscheidenden bzw. wertrelevanten Produkteigenschaften aus. ESL-Produkte
sind in diesem Sinne also nicht nur „l?nger haltbar”, sondern unserer Einsch?tzung nach auch „l?nger frisch”. Dass gerade
die Produktcharakteristika der ESL-Milch den Wünschen der Verbraucher entgegenkommen, zeigt sich an der stetig steigenden
Nachfrage nach diesen Produkten und dem damit einhergehenden Absatzrückgang von herk?mmlich pasteurisierter Frischmilch. Die
Verbraucher haben also durch ihr Kaufverhalten in den letzten Jahren bereits deutlich gemacht, dass sie der ESL-Milch durchaus
positiv gegenüberstehen und sich mit diesem Produktkonzept keineswegs „get?uscht” fühlen, was die hier zusammengefassten Fakten
eindeutig untermauern. 相似文献
27.
B. Lux 《Materialwissenschaft und Werkstofftechnik》1973,4(8):427-433
Protection of High Temperature Metallic Materials against Oxidation , part 2; Protective Layers on Superalloys and High Temperature Materials. The structures of typical protective coatings of superalloys and Nb-alloys are briefly described and possible reasons for their failure are given. The importance of self-healing properties and of the reliability of such protective layers in any technical application is stressed. An order of magnitude of the duration of protection for different alloys is indicated for several coating types. 相似文献
28.
Turchik Jessica A.; Karpenko Veronika; Hammers Dustin; McNamara John R. 《Canadian Metallurgical Quarterly》2007,38(2):158
The rising costs of new psychological tests, increased frequency of test revisions, and difficulty receiving authorization and reimbursement from managed care companies make it increasingly difficult for practitioners to provide the best standard of care to clients when conducting psychological and neuropsychological assessments. Practitioners, especially those in low-income and rural areas, may struggle with handling these practical realities while maintaining ethical standards in conducting psychological assessment. Suggestions for how to manage practical challenges faced by practitioners who provide psychological assessments, such as selecting tests when authorization or reimbursement by a third-party payer is restricted or denied, purchasing psychological tests on a budget, and providing assessments with a limited number of qualified staff are discussed. The authors also provide recommendations for the future prevention of these challenges through work with test developers, test publishing corporations, third-party payers, political action groups, and the psychology profession itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Veronika Kondratieva Seung-Woo Seo 《Communications Letters, IEEE》2007,11(2):149-151
Authentication based on the Merkle tree has been proposed as an energy efficient approach in a resource constrained sensor network environment. It replaces complicated certificate verification with more power efficient hash computations. While previous works assumed complete binary Merkle tree structures, which can be used efficiently only in sensor networks with a specific number of sensor nodes, we investigate incomplete Merkle trees to support any number of sensors. For the incomplete Merkle tree, we demonstrate that an optimal structure can be found through mathematical analysis and simulation. A novel tree indexing scheme is also proposed to reduce communication overhead and save sensors resources during authentication 相似文献
30.
Veronika Ostatná 《Electrochimica acta》2008,53(11):4014-4021
In proteomics and biomedicine fast techniques applicable for preliminary tests of the protein properties and structural changes are sought. Methods of electrochemical analysis have been little utilized in these fields. We show that using constant current chronopotentiometric stripping peak H, minute amounts of denatured and reduced bovine serum albumin (BSA) can be easily discriminated from native BSA. Peak H, which is due to catalytic hydrogen evolution, is greatly enhanced in the presence of non-denaturing concentrations of guanidinium chloride. The course of BSA reduction and denaturation can be followed and traces of the damaged protein can be detected in native BSA samples. 相似文献