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1.
α,ω-Methacrylate-terminated poly(1,3-dioxolane)s (polyDXL) were synthesized by cationic ring-opening polymerization of DXL in the presence of methylene-bis(oxyethylmethacrylate) as transfer agent. If the initiator concentration is small compared with the transfer agent concentration, the molecular weights of the polymers are governed by the ratio of the reacted monomer to the reacted transfer agent. The α,ω-methacrylate-terminated polyDXLs obtained undergo free radical polymerization with formation of polyacetal networks. The properties of the networks as function of the molecular weight of the corresponding prepolymers are reported. 相似文献
2.
Lei Wang Charlotte E. Pelgrim Daniël H. Swart Guido Krenning Adrianus C. van der Graaf Aletta D. Kraneveld Thea Leusink-Muis Ingrid van Ark Johan Garssen Gert Folkerts Saskia Braber 《International journal of molecular sciences》2021,22(9)
Chronic obstructive pulmonary disease (COPD) caused by cigarette smoke (CS) is featured by oxidative stress and chronic inflammation. Due to the poor efficacy of standard glucocorticoid therapy, new treatments are required. Here, we investigated whether the novel compound SUL-151 with mitoprotective properties can be used as a prophylactic and therapeutic treatment in a murine CS-induced inflammation model. SUL-151 (4 mg/kg), budesonide (500 μg/kg), or vehicle were administered via oropharyngeal instillation in this prophylactic and therapeutic treatment setting. The number of immune cells was determined in the bronchoalveolar lavage fluid (BALF). Oxidative stress response, mitochondrial adenosine triphosphate (ATP) production, and mitophagy-related proteins were measured in lung homogenates. SUL-151 significantly decreased more than 70% and 50% of CS-induced neutrophils in BALF after prophylactic and therapeutic administration, while budesonide showed no significant reduction in neutrophils. Moreover, SUL-151 prevented the CS-induced decrease in ATP and mitochondrial mtDNA and an increase in putative protein kinase 1 expression in the lung homogenates. The concentration of SUL-151 was significantly correlated with malondialdehyde level and radical scavenging activity in the lungs. SUL-151 inhibited the increased pulmonary inflammation and mitochondrial dysfunction in this CS-induced inflammation model, which implied that SUL-151 might be a promising candidate for COPD treatment. 相似文献
3.
This study aimed at enhancing knowledge on the fate of diclofenac (DF), together with its main human metabolite 4'-hydroxydiclofenac (4'OHDF), during wastewater treatment by using a laboratory-scale membrane bioreactor (MBR). The reactor was fed continuously with non-radiolabelled diclofenac for a one month period prior to a single pulse of a 14C-radiolabelled solution of DF and 4'OHDF. The solution spike contained approximately 25% 4'OHDF and 65% DF, which corresponds to the ratio observed in municipal sewage, as well as traces of two other metabolites. The radioactivity was monitored for a total of twelve days in the various output streams. The calculation of the complete mass balance in the system demonstrated that the major part of the radioactivity left the reactor with the permeate (88.7%), while 2.1% was recovered in the excess sludge. Negligible amounts were recovered in the off-gas traps and on the membranes. Chromatographic analyses of effluent samples, by means of HPLC-MS coupled in parallel to a radiodetector, displayed a different pattern than the one of the spiked solution. It showed the occurrence of three additional metabolites. 相似文献
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Hoek G Beelen R Kos G Dijkema M van der Zee SC Fischer PH Brunekreef B 《Environmental science & technology》2011,45(2):622-628
There are currently no epidemiological studies on health effects of long-term exposure to ultrafine particles (UFP), largely because data on spatial exposure contrasts for UFP is lacking. The objective of this study was to develop a land use regression (LUR) model for UFP in the city of Amsterdam. Total particle number concentrations (PNC), PM10, PM2.5, and its soot content were measured directly outside 50 homes spread over the city of Amsterdam. Each home was measured during one week. Continuous measurements at a central urban background site were used to adjust the average concentration for temporal variation. Predictor variables (traffic, address density, land use) were obtained using geographic information systems. A model including the product of traffic intensity and the inverse distance to the nearest road squared, address density, and location near the port explained 67% of the variability in measured PNC. LUR models for PM2.5, soot, and coarse particles (PM10, PM2.5) explained 57%, 76%, and 37% of the variability in measured concentrations. Predictions from the PNC model correlated highly with predictions from LUR models for PM2.5, soot, and coarse particles. A LUR model for PNC has been developed, with similar validity as previous models for more commonly measured pollutants. 相似文献
7.
Florenza Lüder Ripoli Annika Mohr Susanne Conradine Hammer Saskia Willenbrock Marion Hewicker-Trautwein Silvia Hennecke Hugo Murua Escobar Ingo Nolte 《International journal of molecular sciences》2016,17(5)
Mammary neoplasms are the tumors most affecting female dogs and women. Formalin-fixed, paraffin-embedded (FFPE) tissues are an invaluable source of archived biological material. Fresh frozen (FF) tissue is considered ideal for gene expression analysis. However, strategies based on FFPE material offer several advantages. Branched-DNA assays permit a reliable and fast workflow when analyzing gene expression. The aim of this study was to assess the comparability of the branched-DNA assay when analyzing certain gene expression patterns between FF and FFPE samples in canine mammary tumors. RNA was isolated from 109 FFPE samples and from 93 FF samples of different canine mammary tissues. Sixteen (16) target genes (Tp53; Myc; HMGA1; Pik3ca; Mcl1; MAPK3; FOXO3; PTEN; GATA4; PFDN5; HMGB1; MAPK1; BRCA2; BRCA1; HMGA2; and Her2) were analyzed via branched-DNA assay (b-DNA). ACTB, GAPDH, and HPRT1 were used as data normalizers. Overall, the relative gene expression of the two different origins of samples showed an agreement of 63%. Still, care should be taken, as FFPE specimens showed lower expression of the analyzed targets when compared to FF samples. The fact that the gene expression in FFPE proved to be lower than in FF specimens is likely to have been caused by the effect of storage time. ACTB had the best performance as a data normalizer. 相似文献
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Dr. Saskia Wolf Dr. Svenja Warnecke Jörg Ehrit Dr. Friedrich Freiberger Prof. Dr. Rita Gerardy‐Schahn Prof. Dr. Chris Meier 《Chembiochem : a European journal of chemical biology》2012,13(17):2605-2615
The cycloSal approach has been used in the past for the synthesis of a range of phosphorylated bioconjugates. In those reports, cycloSal nucleotides were allowed to react with different phosphate nucleophiles. With glycopyranosyl phosphates as nucleophiles, diphosphate‐linked sugar nucleotides were formed. Here, cycloSal‐nucleotides were used to prepare monophosphate‐linked sugar nucleotides successfully in high anomeric purity and high chemical yield. The method was successfully used for the synthesis of three nucleotide glycopyranoses as model compounds. The method was then applied to the syntheses of CMP‐N‐acetyl‐neuraminic acids (CMP‐Neu5NAc) and of four derivatives with different modifications at their amino functions (N‐propanoyl, N‐butanoyl, N‐pentanoyl and N‐cyclopropylcarbonyl). The compounds were used for initial enzymatic studies with a bacterial polysialyltransferase (polyST). Surprisingly, the enzyme showed marked differences in terms of utilisation of the four derivatives. The N‐propanoyl, N‐butanoyl, and N‐pentanoyl derivatives were efficiently used in a first transfer with a fluorescently labelled trisialo‐acceptor. However, elongation of the resulting tetrasialo‐acceptors worsened progressively with the size of the N‐acyl chain. The N‐pentanoyl derivative allowed a single transfer, leading to a capped tetramer. The N‐cyclopropylcarbonyl derivative was not transferred. 相似文献
10.
Prof. Dr.-Ing. F. Taegen Ir. E. Hommes 《Electrical Engineering (Archiv fur Elektrotechnik)》1974,56(4):194-204
Übersicht Ausgehend von der Geometrie der Maschine werden die allgemeinen Gleichungen der Schenkelpol-Synchronmaschine mit Dämpferkäfig aufgestellt und ihre Induktivitäten unter Berücksichtigung der Oberfelder ermittelt. Die Transformation in (o, d, q)-Komponenten läßt erkennen, daß man den Dämpferkäfig durch eine von der Stabzahl je Pol abhängige Anzahl von äquivalenten Ersatzwicklungen in der Längs- und Querachse darstellen kann. Sofern keine Ständernullkomponente auftritt, wird der Dämpferkäfig durch je eine Ersatzwicklung in der Längs- und Querachse verhältnismäßig gut beschrieben. Abschließend wird der Einfluß der Oberfelder auf die Streuung diskutiert.
Verzeichnis der verwendeten Symbole A Transformationsmatrix der Ständergrößen - B Luftspaltinduktion - Amplitude des Ständerfeldes unter Vernachlässigung der Pollücken - B Transformationsmatrix der Käfiggrößen - c Feldfaktor, bezogen auf die Seite der erregenden Wicklung - c Feldfaktor, bezogen auf die der erregenden Wicklung gegenüberliegende Seite - D Bohrungsdurchmesser - i Strom - I Strommatrix - k Konstante nach Gl. (49) - l ideelle Eisenlänge - L Induktivität - L Induktivitätsschwankung - L Induktivitätsmatrix - m, M Gegeninduktivität - M Gegeninduktivitätsschwankung - M e elektromagnetisch erzeugtes Drehmoment - N Anzahl der Dämpferstäbe je Pol - p Polpaarzahl - R Widerstand - R Widerstandsmatrix - t n Nutteilung der Dämpferwicklung im Längenmaß - u Spannung - U Spannungsmatrix - w Anzahl der in Reihe geschalteten Windungen - i ideeller Polbedeckungsfaktor - r Umfangskoordinate des Läufers - Faktor nach Gl. (58) - effektiver einseitiger Luftspalt - räumlicher Winkel zwischen zwei benachbarten Dämpferstäben längs des Polbogens - ; räumlicher Winkel zwischen zwei Randstäben - Verteilungsfaktor der Dämpferwicklung - räumlicher Drehwinkel - 0 Induktionskonstante - Wicklungsfaktor - Spulenfluß - Spulenflußmatrix Indizes a, b, c Bezeichnung der Ständerwicklungsstränge - d Längskomponente des Ständers - D Längskomponente der Dämpferwicklung - f Erreger- - h Haupt- - k Komponente des transformierten Läuferstromes - K Dämpferkäfig - q Querkomponente des Ständers - Q Querkomponente des Dämpferkäfigs - r Läufer - s Ständer - St Stab - Ordnungszahl des Ständerfeldes - v Ordnungszahl des Ständerstrombelages - Streu- - o Nullkomponente - 1, 2, 3, ..., 2pN Bezeichnung der Käfigmaschen Hochgestellte Zeichen p bezogen auf eine Maschine mitp Polpaaren - T transponierte Matrix - nach der ersten Transformation - nach der zweiten Transformation - * konjugiert komplex - ^ Scheitelwert - Drehfeld 相似文献
Contents Starting from the geometry of the machine the general equations of the salient-pole synchronous machine are derived, and its inductances are determined, taking the magnetic field harmonics into account. A transformation to (o, d, q)-components shows, that it is possible to replace the damper winding by equivalent windings in the direct-and quadrature-axis, the number of these equivalent windings depending upon the number of damper bars per pole. If the stator current system does not contain a zero-sequence component, the damper winding can be described comparatively well by one equivalent winding in the direct axis and one in the quadrature axis. Finally, the influence of field harmonics on the leakage inductaces is discussed.
Verzeichnis der verwendeten Symbole A Transformationsmatrix der Ständergrößen - B Luftspaltinduktion - Amplitude des Ständerfeldes unter Vernachlässigung der Pollücken - B Transformationsmatrix der Käfiggrößen - c Feldfaktor, bezogen auf die Seite der erregenden Wicklung - c Feldfaktor, bezogen auf die der erregenden Wicklung gegenüberliegende Seite - D Bohrungsdurchmesser - i Strom - I Strommatrix - k Konstante nach Gl. (49) - l ideelle Eisenlänge - L Induktivität - L Induktivitätsschwankung - L Induktivitätsmatrix - m, M Gegeninduktivität - M Gegeninduktivitätsschwankung - M e elektromagnetisch erzeugtes Drehmoment - N Anzahl der Dämpferstäbe je Pol - p Polpaarzahl - R Widerstand - R Widerstandsmatrix - t n Nutteilung der Dämpferwicklung im Längenmaß - u Spannung - U Spannungsmatrix - w Anzahl der in Reihe geschalteten Windungen - i ideeller Polbedeckungsfaktor - r Umfangskoordinate des Läufers - Faktor nach Gl. (58) - effektiver einseitiger Luftspalt - räumlicher Winkel zwischen zwei benachbarten Dämpferstäben längs des Polbogens - ; räumlicher Winkel zwischen zwei Randstäben - Verteilungsfaktor der Dämpferwicklung - räumlicher Drehwinkel - 0 Induktionskonstante - Wicklungsfaktor - Spulenfluß - Spulenflußmatrix Indizes a, b, c Bezeichnung der Ständerwicklungsstränge - d Längskomponente des Ständers - D Längskomponente der Dämpferwicklung - f Erreger- - h Haupt- - k Komponente des transformierten Läuferstromes - K Dämpferkäfig - q Querkomponente des Ständers - Q Querkomponente des Dämpferkäfigs - r Läufer - s Ständer - St Stab - Ordnungszahl des Ständerfeldes - v Ordnungszahl des Ständerstrombelages - Streu- - o Nullkomponente - 1, 2, 3, ..., 2pN Bezeichnung der Käfigmaschen Hochgestellte Zeichen p bezogen auf eine Maschine mitp Polpaaren - T transponierte Matrix - nach der ersten Transformation - nach der zweiten Transformation - * konjugiert komplex - ^ Scheitelwert - Drehfeld 相似文献