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排序方式: 共有374条查询结果,搜索用时 15 毫秒
61.
N Yuasa Y Nimura N Hayakawa J Kamiya S Maeda S Kondo T Nagasaka 《Canadian Metallurgical Quarterly》1997,44(17):1262-1266
A case of multiple hepatic cysts of the periductal gland located along the left intrahepatic bile duct is described. Ultrasonography and computed tomography disclosed many cystic lesions along the left portal vein in the left lateral segment of the liver. Percutaneous transhepatic cholangiography showed many compressed lesions. The resected specimen revealed multiple cysts of 2-7mm in diameter along the intrahepatic bile duct. Microscopically, cysts within the large Glisson's capsule were intermixed with lobuli of the periductal glands, thus suggesting periductal gland origin. Histopathological features of these cysts were similar to those of "multiple hilar cysts" reported by Nakanuma, but lack of portal hypertension and underlying chronic liver disease is the significant characteristics in this case which is different from "multiple hilar cysts". 相似文献
62.
Long‐Lived Flexible Displays Employing Efficient and Stable Inverted Organic Light‐Emitting Diodes 下载免费PDF全文
Hirohiko Fukagawa Tsubasa Sasaki Toshimitsu Tsuzuki Yoshiki Nakajima Tatsuya Takei Genichi Motomura Munehiro Hasegawa Katsuyuki Morii Takahisa Shimizu 《Advanced materials (Deerfield Beach, Fla.)》2018,30(28)
Although organic light‐emitting diodes (OLEDs) are promising for use in applications such as in flexible displays, reports of long‐lived flexible OLED‐based devices are limited due to the poor environmental stability of OLEDs. Flexible substrates such as plastic allow ambient oxygen and moisture to permeate into devices, which degrades the alkali metals used for the electron‐injection layer in conventional OLEDs (cOLEDs). Here, the fabrication of a long‐lived flexible display is reported using efficient and stable inverted OLEDs (iOLEDs), in which electrons can be effectively injected without the use of alkali metals. The flexible display employing iOLEDs can emit light for over 1 year with simplified encapsulation, whereas a flexible display employing cOLEDs exhibits almost no luminescence after only 21 d with the same encapsulation. These results demonstrate the great potential of iOLEDs to replace cOLEDs employing alkali metals for use in a wide variety of flexible organic optoelectronic devices. 相似文献
63.
The triad-level sequence analysis of poly(ethylene/1,4-cyclohexanedimethylene terephthalate) copolymer was reported in a solvent system of o-chlorophenol/deuterated chloroform mixture (50/50 v/v) at 80 °C using 600 MHz 1H NMR. The well-resolved alcoholic CH2 proton peak of the glycol units was observed, which made the detailed sequence analysis possible. The peaks of the cis- and trans-forms of the 1,4-cyclohexanedimethylene glycol units were split into the triad sequence in the chain and could be assigned by a comparison of the spectra with those of homopolymers and by an additional two-dimensional heteronuclear multiple bond correlation observation. The triad sequence distributions centered on 1,4-cyclohexanedimethylene glycol units were determined, which was independent of the cis- and trans-forms of the units and controlled according to Bernoullian statistics. 相似文献
64.
The aim of the present study was to compare the effects of a low-fat diet enriched with oleic acid to those of a low-fat diet
enriched with linoleic acid on fasting lipids, postprandial lipemia, and oxidative susceptibility of low-density lipoprotein
(LDL) in patients with type 2 diabetes mellitus (DM). In a 3-wk randomized crossover study, eight patients with type 2 DM
were given an experimental low-fat diet enriched with either oleic acid or linoleic acid. The oleic-acid-enriched diet contained
5, 15, and 5% energy from saturated, monounsaturated, and polyunsaturated fatty acids, and the linoleic-acid-enriched diet
contained 5, 5, and 15% energy from saturated, monounsaturated, and polyunsaturated fatty acids, respectively. In addition
to evaluating the fasting lipids and oxidative susceptibility of LDL, we evaluated postprandial lipemia using an oral fat
load at the end of each 3-wk dietary phase. There were no significant differences in fasting lipid profile or lag time of
LDL oxidation between the two experimental dietary phases. The average and maximal increments of remnant-like particle (RLP)
cholesterol levels during oral fat load were significantly higher after the oleic-acid-enriched dietary phase than after the
linoleic-acid-enriched dietary phase. The area under the curve of RLP cholesterol was also significantly larger after the
oleicacid-enriched dietary phase than after the linoleic-acid-enriched dietary phase. These results suggest that the oleic-acidenriched
diet was associated with increased formation of postprandial chylomicron remnants compared with the linoleicacid-enriched
diet. 相似文献
65.
Susumu Shima Hidetoshi Kotera Kei Kamitani Toshimitsu Bando 《Metals and Materials International》1998,4(3):404-407
This paper deals with development of an incremental deep drawing process. On a newly developed incremental deep drawing set-up, the aluminium sheets are formed; the forming is carried out by deep-drawing the blank as in the conventional method but incrementally. Fractures at the punch or die corner in the blank may or may not occur depending on the conditions; the process parameters involved are punch size, punch corner radius, increment in punch displacement, blank holding force or pressure, etc. It is thus shown that different shapes are formed by one set of common tools. It is thereby confirmed that incremental deep drawing is possible without using a particular tool set for a particular shape. 相似文献
66.
A novel multi-model neuro-fuzzy-based MPPT for three-phase grid-connected photovoltaic system 总被引:1,自引:0,他引:1
This paper presents a novel methodology for Maximum Power Point Tracking (MPPT) of a grid-connected 20 kW photovoltaic (PV) system using neuro-fuzzy network. The proposed method predicts the reference PV voltage guarantying optimal power transfer between the PV generator and the main utility grid. The neuro-fuzzy network is composed of a fuzzy rule-based classifier and three multi-layered feed forwarded Artificial Neural Networks (ANN). Inputs of the network (irradiance and temperature) are classified before they are fed into the appropriated ANN for either training or estimation process while the output is the reference voltage. The main advantage of the proposed methodology, comparing to a conventional single neural network-based approach, is the distinct generalization ability regarding to the nonlinear and dynamic behavior of a PV generator. In fact, the neuro-fuzzy network is a neural network based multi-model machine learning that defines a set of local models emulating the complex and nonlinear behavior of a PV generator under a wide range of operating conditions. Simulation results under several rapid irradiance variations proved that the proposed MPPT method fulfilled the highest efficiency comparing to a conventional single neural network and the Perturb and Observe (P&O) algorithm dispositive. 相似文献
67.
68.
Acrolein formation in the oxidation of ethane over silica catalysts supporting iron and cesium 总被引:1,自引:0,他引:1
Kiyoharu Nakagawa Yonghong Teng Zhen Zhao Yusuke Yamada Atsushi Ueda Toshimitsu Suzuki Tetsuhiko Kobayashi 《Catalysis Letters》1999,63(1-2):79-82
A significant yield of aldehydes was obtained by the partial oxidation of ethane over alkali‐modified Fe/SiO2 catalysts at 475°C (<2% in the case of Cs–Fe/SiO2). Not only acetaldehyde and formaldehyde but also acrolein were produced in the present system. There are no reports regarding the catalysts for the direct acrolein formation from partial oxidation of ethane. Such significant promoting effect of alkali‐modified Fe/SiO2 catalysts in the partial oxidation of hydrocarbons has never been observed. Aldol‐type condensation for formation of acrolein could occur in the partial oxidation of ethane over alkali‐modified Fe/SiO2 catalysts. This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
69.
A highly transparent and thermally stable copolymer of 1‐adamantyl methacrylate and styrene 下载免费PDF全文
Thermal and optical properties of copolymers of 1‐adamantyl methacrylate (AdMA) and styrene (St) prepared by free radical polymerization in the bulk are investigated. The copolymer forms an azeotrope when the composition is AdMA/St = 55/45 mol%. The glass transition temperature and decomposition temperature of the azeotropic copolymer are 170 and ca 340 °C, respectively. The refractive index increases nonlinearly with St content from 1.522 to 1.591. The light scattering loss at 633 nm is 28.1 dB km?1, which is less than half of that of polystyrene. The total optical loss including molecular vibrational absorption, which is evaluated using a copolymer‐based optical fiber, is 292–645 dB km?1 at 500–700 nm. These values correspond to transmittances of 86–93% for a 1 m optical path length. © 2014 Society of Chemical Industry 相似文献
70.
The angular distribution of inelastically scattered electrons following the carbon K-shell ionization of a carbon nanotube (CNT) has been studied by using an energy-filtered transmission electron microscope. The energy-filtered scattering patterns of the CNT, whose cylindrical axis is oriented in the perpendicular direction with respect to the incident-electron beam, show anisotropic angular distributions caused by the p symmetry in the pi* and sigma* unoccupied states into which a K electron jumps, and the cylindrical shape of the CNT. Corresponding inelastic scattering cross sections, differential in solid angle, have been calculated within the first Born approximation by considering that each carbon atom has three, mutually orthogonal, unoccupied p orbitals, which are oriented in directions perpendicular or parallel to the tube surface. The observed angular patterns agree well with theoretical results, which are linear combinations of the differential cross sections accompanied by the transitions to pi* and sigma* states. A series of the fittings of the experimental patterns at successive values of energy loss provides magnitudes of the pi* and sigma* components, which can be called partial electron energy-loss spectra accompanied by the transitions to the pi* and sigma* states. 相似文献