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PM Hanno 《Canadian Metallurgical Quarterly》1994,21(1):89-91
Limited data and an accumulated body of anecdotal experience with the tricyclic class of antidepressants suggest that this group of drugs (especially amitriptyline) may be an effective treatment modality in nonulcerative interstitial cystitis. Both the ease of administration and the relatively rapid onset of relief make these types of drugs appropriate to consider for first-line therapy after bladder distention has failed. 相似文献
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A national survey of school psychologists' acceptability of psychological assessment techniques in the area of externalizing problem behaviors was examined. School psychologists' ratings of 2 procedures, Behavioral Assessment (BA) and Traditional Assessment (TA), were compared using an analog case study methodology. Using a random sample of 500 National Association of School Psychologists members from the 1991–1992 membership directory, 339 Ss completed the Assessment Rating Profile after reading a hypothetical case summary describing a student with suspected externalizing problem behaviors. Results indicated statistically significant differences between assessment methods and ratings of acceptability. BA procedures were found to be more acceptable than TA procedures. Implications related to the acceptability of psychological assessment techniques, as well as implications for school psychology practitioners are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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MC Huysmans C Longbottom H Hintze EH Verdonschot 《Canadian Metallurgical Quarterly》1998,32(5):330-336
We investigated the lipid metabolism in primary cultured hepatocytes to elucidate the causes of hyperlipidemia, increased cholesteryl esters, and decreased triglyceride levels in the livers of daunomycin-nephrotic rats. The incorporation of 14C-palmitate into phospholipids and triglycerides in primary cultured hepatocytes and medium was similar in daunomycin-nephrotic and control rats. The incorporation of 14C-acetate into phospholipids, triglycerides, cholesterol, cholesteryl esters, and total fatty acids in primary cultured hepatocytes was increased in daunomycin-nephrotic rats. The radioactivity of phospholipids, triglycerides, cholesterol, cholesteryl esters, and very-low-density lipoprotein lipids in medium was increased in the hepatocytes of daunomycin-nephrotic rats using 14C-acetate as a precursor. The increased cholesterogenesis and the increased secretion of triglycerides synthesized from acetate by hepatocytes may be due to an increased cholesteryl ester content and a decreased triglyceride content in the livers of daunomycin-nephrotic rats. The increased secretion of lipids synthesized from acetate by hepatocytes may be due to increased accumulation of lipids in serum and very-low-density lipoprotein in daunomycin-nephrotic rats. 相似文献
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Hanno Sachsse 《Holz als Roh- und Werkstoff》1964,22(5):169-174
Zusammenfassung In Erg?nzung früberer Untersuchungen wurden von methacrylat-eingebettetem Zugholz- und Normalfasergewebe vonPopulus euramericana cv.regenerata ultradünne Quer- und L?ngsschnitte hergestellt. Die elektronen-mikroskopische Untersuchung zeigt, da? die Zellwand der Zugholzfaser
aus Mittellamelle, Prim?rwand, den Sekund?rwandschichten 1 bis 3 sowie einer Immenseitigen Abschlu?lamelle besteht. Die S3 stellt dabei die für Zugholzfaser charakteristische gelatin?se (G-)Schicht dar. Die Struktur dieser G-Schicht kann elektronenmikroskopisch
nur durch Herausl?sen des Einbettungsmediums deutlich sichtbar gemacht werden. In solcher Weise behandelte Ultradünnschnitte
lassen erkennen, da? die G-Schicht eine Wabenstruktur besitzt, in der einzelne cellulosische Lamellen durch Haftpunkte miteinander
verbunden sind. Wahrscheinlich sind die Kammern des Wabensystems mit quellbaren Interlamellarsubstanzen ausgefüllt, die in
Verbindung mit der Wabenstruktur die bekannten L?ngszugspannungen im Zugholz verursachen k?nnten. Die Entstehung dieser Spannungen
ist sowohl als Folge einer Quellung, wie auch als Folge einer Entquellung der G-Schicht denkbar. Die M?glichkeit von Strukturver?nderungen
durch die angewendeten Pr?parations vefahren wird ausführlich er?rtert. Es wird nachgewiesen, da? die beschriebeue Wabenstruktur
der G-schicht nicht den wabigen Strukturen entspricht, die sich durch S?urebehandlung in der zentralen Sekund?rwandschicht
normaler Faserzellen erzeugen lassen.
Beitrag zu den Verhandlungen der Arbeitsgruppe Wood Quality der IUFRO-Sektion 41 in Madison, USA, vom 11. bis 13. September 1963. 相似文献
The submicroscopic structure of the fibre cellwall in poplar tensionwood
Summary In addition to preliminary investigations, ultrathin cross-and and longitudinal sections of tensionwood and normal wood tissue from Populus euramericana cv. regenerata were investigated. These tissues were embedded in methacrylate and examined with an electronmicroscope. It was found that the cell wall of tensionwood fibres of this species is composed of middle lamella, primary wall, and secondary wall. The latter consists of three layers (S1, S2, S3) and is bordered on the lumen side by a terminating lamella. In tensionwood, the S3 appears as a characteristic gelatinous (G) layer. The detailed structure of this G-layer can be clearly seen only when the embedding material is dissolved, its density being very similar to that of the cellulose lamellae of the G-layer. The methacrylate embedding material having been removed, is was found that the G-layer posseses a honeycomb-structure in which the individual cellulose lamellae are firmly connected at irregularly spaced intervals. It is supposed that the interlamellar spaces of this honeycomb-structured G-layer are filled with substances which are able to swell and shrink. It is postulated here that the inherent tensional strains and the resulting longitudinal contraction of tensionwood fibers and tissue, commonly observed, might be caused by either the swelling or shrinking of interlamellar substances within the G-layer. Swelling might cause longitudinal contraction, if these substances swell mostly in radial direction. This radial swelling results in a radial expansion and, consequently, longitudinal contraction of the individual cavities of the honeycomb structure. On the other hand, the commonly observed longitudinal confraction of tensionwood fibres and tissue might also be explained by shrinking. In this case, the interlamellar substances must be mostly isotropic, and thus their shrinking and consequently that of the tensionwood tissue would occur in all directions. The methods used to establish that the honeycomb structure of the G-layer is not an artifact of the preparation, are also described. It is proven that the G-layer structure as described in this paper is not the same as the honeycomb structure produced by the treating of fibre cells of normal wood tissue with acid.
Beitrag zu den Verhandlungen der Arbeitsgruppe Wood Quality der IUFRO-Sektion 41 in Madison, USA, vom 11. bis 13. September 1963. 相似文献
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C.H. Swanson T. Stimpfling A.‐L. Troutier‐Thulliez H. Hintze‐Bruening F. Leroux 《应用聚合物科学杂志》2013,128(5):2954-2960
Nitrate layered double hydroxide (LDH) phase Zn2Al(OH)6(NO3)·2H2O is successfully exfoliated in the presence of polyester under mild conditions using water as essential solvent and at room temperature under air. From small angle X‐ray scattering spectroscopy a total exfoliation is found to be achieved using up to 10 wt % LDH, while intercalated polymer nanocomposite structures largely extended up to 14 nm are observed for loading ranging from 10 to 20 wt %. The process is found to be explained by the diffusion of the polymer chain into the interlayer host structure. Starting from an initial value of 0.89 nm, ≈3, 7, 10, 14, and 20 nm transient interleaved nanostructures are formed without any carbonate uptake. The collective gap distance is certainly due to a defined number of polymer chains diffusing into the LDH interstices. Similarly, starting from an aqueous polyester solution highly concentrated in LDH nitrate phase up to 50% w.w, successive dilutions yield platelet exfoliation, thus rendering a smooth chemistry process attractive for potential applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献