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排序方式: 共有460条查询结果,搜索用时 15 毫秒
451.
Liuliu Du Stuart Batterman Edith Parker Christopher Godwin Jo-Yu Chin Ashley O’Toole Thomas Robins Wilma Brakefield-Caldwell Toby Lewis 《Building and Environment》2011
Asthma can be exacerbated by environmental factors including airborne particulate matter (PM) and environmental tobacco smoke (ETS). We report on a study designed to characterize PM levels and the effectiveness of filters on pollutant exposures of children with asthma. 126 households with an asthmatic child in Detroit, Michigan, were recruited and randomized into control or treatment groups. Both groups received asthma education; the latter also received a free-standing high efficiency air filter placed in the child’s bedroom. Information regarding the home, emission sources, and occupant activities was obtained using surveys administered to the child’s caregiver and a household inspection. Over a one week period, we measured PM, carbon dioxide (CO2), environmental tobacco smoke (ETS) tracers, and air exchange rates (AERs). Filters were installed at midweek. Before filter installation, PM concentrations averaged 28 μg m−3, number concentrations averaged 70,777 and 1471 L−1 in 0.3–1.0 and 1–5 μm size ranges, respectively, and the median CO2 concentration was 1018 ppm. ETS tracers were detected in 23 of 38 homes where smoking was unrestricted and occupants included smokers and, when detected, PM concentrations were elevated by an average of 15 μg m−3. Filter use reduced PM concentrations by an average of 69–80%. Simulation models representing location conditions show that filter air flow, room volume and AERs are the key parameters affecting PM removal, however, filters can achieve substantial removal in even "worst" case applications. While PM levels in homes with asthmatic children can be high, levels can be dramatically reduced using filters. 相似文献
452.
Elodie Ehret Yannick Jger Chlo Sergi Anne-Marie Mrillat Thibaud Peyrollaz Deepika Anand Qing Wang Frderique Ino Marc Maillard Stephan Kellenberger Ivan Gautschi Roman Szabo Thomas H. Bugge Lotte K. Vogel Edith Hummler Simona Frateschi 《International journal of molecular sciences》2022,23(12)
The serine protease prostasin (CAP1/Prss8, channel-activating protease-1) is a confirmed in vitro and in vivo activator of the epithelial sodium channel ENaC. To test whether proteolytic activity or CAP1/Prss8 abundance itself are required for ENaC activation in the kidney, we studied animals either hetero- or homozygous mutant at serine 238 (S238A; Prss8cat/+ and Prss8cat/cat), and renal tubule-specific CAP1/Prss8 knockout (Prss8PaxLC1) mice. When exposed to varying Na+-containing diets, no changes in Na+ and K+ handling and only minor changes in the expression of Na+ and K+ transporting protein were found in both models. Similarly, the α- or γENaC subunit cleavage pattern did not differ from control mice. On standard and low Na+ diet, Prss8cat/+ and Prss8cat/cat mice exhibited standard plasma aldosterone levels and unchanged amiloride-sensitive rectal potential difference indicating adapted ENaC activity. Upon Na+ deprivation, mice lacking the renal CAP1/Prss8 expression (Prss8PaxLC1) exhibit significantly decreased plasma aldosterone and lower K+ levels but compensate by showing significantly higher plasma renin activity. Our data clearly demonstrated that the catalytic activity of CAP1/Prss8 is dispensable for proteolytic ENaC activation. CAP1/Prss8-deficiency uncoupled ENaC activation from its aldosterone dependence, but Na+ homeostasis is maintained through alternative pathways. 相似文献
453.
Heinrich Leopold und Edith Wagner 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1942,83(6):487-512
Zusammenfassung Die Grundlage für vorliegende Untersuchungen bildete ein aus der Industrie stammendes, aus Rohrzucker hergestelltes Caramelzuckerpräparat für Diabetiker. Zuerst wird über Erfahrungen berichtet, die über die Verwendung solcher Produkte in der Diabetestherapie vorliegen. Anschließend folgt eine Übersicht über die bisher bekannten, an Caramelprodukten aus Rohrzucker gewonnenen Forschungsergebnisse, die vielfach nicht miteinander in Einklang zu bringen sind. Es ist noch nicht möglich, über den Verlauf der Caramelisierung und die dabei gebildeten Substanzen eine klare Vorstellung zu gewinnen. Hierauf werden Versuche zur Herstellung von Caramelzuckerpräparaten, die dem Originalprodukt möglichst ähnlich sind, beschrieben. Eine an diesem und an selbst hergestellten Präparaten durchgeführte orientierende Analyse zeigt, daß sich mit Hilfe der üblichen Bestimmungsmethoden kein brauchbares Ergebnis erzielen läßt. Noch deutlicher erhellt das Verwickeltsein der Verhältnisse aus Untersuchungen über die Abhängigkeit der Analysenergebnisse von der Art der Bestimmungsmethode. Aus Versuchen über die gegenseitige Beeinflussung der einzelnen Bestandteile bei der reduktometrischen Bestimmung ließen sich keine Regelmäßigkeiten ablesen. Es folgt dann eine Beschreibung der analytischen Bestimmungsmethoden und Reaktionen, die an einigen als Bestandteile von Caramelzuckern erkannten Stoffen und Caramelpräparaten zur Anwendung gelangten. Die an ersteren gemachten Feststellungen ermöglichten eine weitgehende Deutung der an einem Caramelzucker und dessen unvergärbarem Anteil gewonnenen Analysenergebnisse. Es gelang, den Trockensubstanzgehalt des Präparates bis auf einige Prozente in mehr oder minder bekannte Substanzen aufzuteilen. Die Analyse eines zweiten Caramelproduktes zeigt, daß relativ kleine Änderungen der Herstellungsbedingungen deutliche prozentuelle Verschiebungen der einzelnen Anteile zur Folge haben. Die in Rede stehenden Caramelzucker gehören zu den schwach caramelisierten Produkten, die vollkommen wasserlöslich sind und keine kolloiden Bestandteile enthalten. 相似文献
454.
The Nitrile Carboxamide Rearrangement and the Formation of Heterocycles via Cyano-cyclohexenyl-urea Anthranilic amide and cyanogen bromide form Cyano-phenyl-urea ( 7 ) via Nitrile Carboxamide Rearrangement. Cyclisation of cyano-cyclohexenyl-urea ( 4 ) yields 4-amino-2,3,5,6,7,8-hexahydroquinazolin-2-one ( 10 ). 4 and amines form N-cyano-cyclohexenyl-N'-alkyl-ureas ( 11a–e ) or 3-alkyl-4-amino-hexahydroquinazolin-2-ones ( 12a–g ). 4 and α-aminoacids yield octahydro-imidazolo-quinazolindiones ( 14a–b ). Oxo-cyclohexane-2-carboxamide ( 1 ) and amino benzimidazole form hexahydrobenzimidazo-quinazolinone 17 . 相似文献
455.
Edith Tretschk Navami Kairanda Mallikarjun B R Rishabh Dabral Adam Kortylewski Bernhard Egger Marc Habermann Pascal Fua Christian Theobalt Vladislav Golyanik 《Computer Graphics Forum》2023,42(2):485-520
3D reconstruction of deformable (or non-rigid) scenes from a set of monocular 2D image observations is a long-standing and actively researched area of computer vision and graphics. It is an ill-posed inverse problem, since—without additional prior assumptions—it permits infinitely many solutions leading to accurate projection to the input 2D images. Non-rigid reconstruction is a foundational building block for downstream applications like robotics, AR/VR, or visual content creation. The key advantage of using monocular cameras is their omnipresence and availability to the end users as well as their ease of use compared to more sophisticated camera set-ups such as stereo or multi-view systems. This survey focuses on state-of-the-art methods for dense non-rigid 3D reconstruction of various deformable objects and composite scenes from monocular videos or sets of monocular views. It reviews the fundamentals of 3D reconstruction and deformation modeling from 2D image observations. We then start from general methods—that handle arbitrary scenes and make only a few prior assumptions—and proceed towards techniques making stronger assumptions about the observed objects and types of deformations (e.g. human faces, bodies, hands, and animals). A significant part of this STAR is also devoted to classification and a high-level comparison of the methods, as well as an overview of the datasets for training and evaluation of the discussed techniques. We conclude by discussing open challenges in the field and the social aspects associated with the usage of the reviewed methods. 相似文献
456.
About the Reaction between Hydrazines and Aminohydroxy-hydrobenzoxazol. Synthesis of Azoolefines By the reaction of 1-hydroxy-2-oxocyclohexane-carboxamide ( 1 ) with cyanamide 2-amino-7a-carbamoyl-3a-hydroxy-3a,4a,5,6,7,7a-hexahydrobenzoxazole ( 2 ) is formed. Compound 2 and arylhydrazine-hydrochloride yield 1-carbamoyl-2-arylazocyclohex-1-ene ( 4a , b ). In morpholine azocompounds 4a , b rearrange to hydrazones 5a , b . Compound 2 and hydrazine yield 4-(2-carbamoyl-cyclohexyl)-semicarbazide ( 10 ), 10 forms perhydroquinazoline-2,4-dione ( 11 ) by oxidation with iodine. 2 and cyanic acid yield the urea derivative 12 . 2 and arylamine-hydrochloride afford the 2-arylamino-3a-hydroxy-7a-carbamoyl-hexahydrobenzoxazoles 13a , b . By fragmentation and “Dimroth-rearrangement” of 2 tetrahydrobenzoimidazolone, ( 14 ) is formed, 12 gives 1-carbamoyl-tetrahydrobenzoimidazolone ( 15 ). 2 and m-nitrobenzaldehyde yield “Schiff-base” 16 . 2 and hydroxylamine sulphate form 2′-amino-2-hydroximino-cyclohexane-spiro-5′-oxazolin-4′-one ( 18 ) 18 and phenylhydrazine hydrochloride yield 1-phenylazo-2-ureido-carboxy-cyclohex-1-ene ( 19 ). 相似文献
457.
Klaus Sommermeyer Ulrich Hildebrand Franz Cech Edith Pfitzer Klaus Henning Burghard Weidler 《Starch - St?rke》1992,44(5):173-179
Fine Structure and Hyperfine Structure of Clinically Applied Hydroxyethyl Starch. The Mark-Houwink-relationships for different samples of clinically used hydroxyethyl starches were established by multi-detection HPGPC. In combination with the degree of branching, the degrees of substitution DS and the molar substitution MS for the different molecular regions were measured by gas chromatographic methylation analysis. Within the molecular regions of non reducing anhydroglucose units, branching units and linear units we found characteristic differences. For hydroxyethyl starches which were prepared from enzymatically hydrolyzed waxy maize starch by α-Amylase, we found a significantly higher degree of branching than for samples prepared by acid hydrolysis. The clinical relevance of these results is discussed. 相似文献
458.
The Bromination of Cyclohexanone-2-carboxamide Cyclohexanone-2-carboxamide with bromine forms 6-bromo-cyclohexanone-2-carboxamide ( 2 ) or 2-bromo-cyclohexanone-2-carboxamide ( 3 ). Via Faworski-rearrangement the reaction of 2 and ammonia or amines gives trans-cyclopentanedicarboxamides ( 5a – f ). 3 and thiourea form the aminothiazole derivative 6 . Pyridinium salt 7 is formed by reaction of 2 and pyridine. 7 and phenylhydrazine form the phenyl-indazolonoyl-hydrazine 8. 1 and sodiumhypochlorite yield 2-hydroxy-cyclohexanone-2-carboxamide ( 9 ). 相似文献
459.
Filipa Mota Tamas Yelland Jennie A. Hutton Jennifer Parker Anastasia Patsiarika A. W. Edith Chan Andrew O'Leary Constantina Fotinou John F. Martin Ian C. Zachary Snezana Djordjevic Paul Frankel David L. Selwood 《Chembiochem : a European journal of chemical biology》2022,23(1):e202100463
Vascular endothelial growth factors (VEGFs) regulate significant pathways in angiogenesis, myocardial and neuronal protection, metabolism, and cancer progression. The VEGF-B growth factor is involved in cell survival, anti-apoptotic and antioxidant mechanisms, through binding to VEGF receptor 1 and neuropilin-1 (NRP1). We employed surface plasmon resonance technology and X-ray crystallography to analyse the molecular basis of the interaction between VEGF-B and the b1 domain of NRP1, and developed VEGF-B C-terminus derived peptides to be used as chemical tools for studying VEGF-B - NRP1 related pathways. Peptide lipidation was used as a means to stabilise the peptides. VEGF-B-derived peptides containing a C-terminal arginine show potent binding to NRP1-b1. Peptide lipidation increased binding residence time and improved plasma stability. A crystal structure of a peptide with NRP1 demonstrated that VEGF-B peptides bind at the canonical C-terminal arginine binding site. VEGF-B C-terminus imparts higher affinity for NRP1 than the corresponding VEGF-A165 region. This tight binding may impact on the activity and selectivity of the full-length protein. The VEGF-B167 derived peptides were more effective than VEGF-A165 peptides in blocking functional phosphorylation events. Blockers of VEGF-B function have potential applications in diabetes and non-alcoholic fatty liver disease. 相似文献
460.